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xenia/third_party/crunch/crnlib/crn_dxt1.cpp

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Adding Crunch at r319.
2014-01-21 07:02:34 +00:00
// File: crn_dxt1.cpp
// See Copyright Notice and license at the end of inc/crnlib.h
//
// Notes:
// This class is not optimized for performance on small blocks, unlike typical DXT1 compressors. It's optimized for scalability and quality:
// - Very high quality in terms of avg. RMSE or Luma RMSE. Goal is to always match or beat every other known offline DXTc compressor: ATI_Compress, squish, NVidia texture tools, nvdxt.exe, etc.
// - Reasonable scalability and stability with hundreds to many thousands of input colors (including inputs with many thousands of equal/nearly equal colors).
// - Any quality optimization which results in even a tiny improvement is worth it -- as long as it's either a constant or linear slowdown.
// Tiny quality improvements can be extremely valuable in large clusters.
// - Quality should scale well vs. CPU time cost, i.e. the more time you spend the higher the quality.
#include "crn_core.h"
#include "crn_dxt1.h"
#include "crn_ryg_dxt.hpp"
#include "crn_dxt_fast.h"
#include "crn_intersect.h"
#include "crn_vec_interval.h"
namespace crnlib
{
//-----------------------------------------------------------------------------------------------------------------------------------------
static const int16 g_fast_probe_table[] = { 0, 1, 2, 3 };
static const uint cFastProbeTableSize = sizeof(g_fast_probe_table) / sizeof(g_fast_probe_table[0]);
static const int16 g_normal_probe_table[] = { 0, 1, 3, 5, 7 };
static const uint cNormalProbeTableSize = sizeof(g_normal_probe_table) / sizeof(g_normal_probe_table[0]);
static const int16 g_better_probe_table[] = { 0, 1, 2, 3, 5, 9, 15, 19, 27, 43 };
static const uint cBetterProbeTableSize = sizeof(g_better_probe_table) / sizeof(g_better_probe_table[0]);
static const int16 g_uber_probe_table[] = { 0, 1, 2, 3, 5, 7, 9, 10, 13, 15, 19, 27, 43, 59, 91 };
static const uint cUberProbeTableSize = sizeof(g_uber_probe_table) / sizeof(g_uber_probe_table[0]);
//-----------------------------------------------------------------------------------------------------------------------------------------
dxt1_endpoint_optimizer::dxt1_endpoint_optimizer() :
m_pParams(NULL),
m_pResults(NULL),
m_pSolutions(NULL),
m_perceptual(false),
m_has_color_weighting(false),
m_all_pixels_grayscale(false)
{
m_low_coords.reserve(512);
m_high_coords.reserve(512);
m_unique_colors.reserve(512);
m_temp_unique_colors.reserve(512);
m_unique_packed_colors.reserve(512);
m_norm_unique_colors.reserve(512);
m_norm_unique_colors_weighted.reserve(512);
m_lo_cells.reserve(128);
m_hi_cells.reserve(128);
}
void dxt1_endpoint_optimizer::clear()
{
m_pParams = NULL;
m_pResults = NULL;
m_pSolutions = NULL;
if (m_unique_color_hash_map.get_table_size() > 8192)
m_unique_color_hash_map.clear();
else
m_unique_color_hash_map.reset();
if (m_solutions_tried.get_table_size() > 8192)
m_solutions_tried.clear();
m_unique_colors.resize(0);
m_has_transparent_pixels = false;
m_total_unique_color_weight = 0;
m_norm_unique_colors.resize(0);
m_mean_norm_color.clear();
m_norm_unique_colors_weighted.resize(0);
m_mean_norm_color_weighted.clear();
m_principle_axis.clear();
m_total_evals = 0;
m_all_pixels_grayscale = false;
m_has_color_weighting = false;
m_perceptual = false;
}
bool dxt1_endpoint_optimizer::handle_all_transparent_block()
{
m_pResults->m_low_color = 0;
m_pResults->m_high_color = 0;
m_pResults->m_alpha_block = true;
memset(m_pResults->m_pSelectors, 3, m_pParams->m_num_pixels);
return true;
}
// All selectors are equal. Try compressing as if it was solid, using the block's average color, using ryg's optimal single color compression tables.
bool dxt1_endpoint_optimizer::try_average_block_as_solid()
{
uint64 tot_r = 0;
uint64 tot_g = 0;
uint64 tot_b = 0;
uint total_weight = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
{
uint weight = m_unique_colors[i].m_weight;
total_weight += weight;
tot_r += m_unique_colors[i].m_color.r * weight;
tot_g += m_unique_colors[i].m_color.g * weight;
tot_b += m_unique_colors[i].m_color.b * weight;
}
const uint half_total_weight = total_weight >> 1;
uint ave_r = static_cast<uint>((tot_r + half_total_weight) / total_weight);
uint ave_g = static_cast<uint>((tot_g + half_total_weight) / total_weight);
uint ave_b = static_cast<uint>((tot_b + half_total_weight) / total_weight);
uint low_color = (ryg_dxt::OMatch5[ave_r][0]<<11) | (ryg_dxt::OMatch6[ave_g][0]<<5) | ryg_dxt::OMatch5[ave_b][0];
uint high_color = (ryg_dxt::OMatch5[ave_r][1]<<11) | (ryg_dxt::OMatch6[ave_g][1]<<5) | ryg_dxt::OMatch5[ave_b][1];
bool improved = evaluate_solution(dxt1_solution_coordinates((uint16)low_color, (uint16)high_color), true, &m_best_solution);
if ((m_pParams->m_use_alpha_blocks) && (m_best_solution.m_error))
{
low_color = (ryg_dxt::OMatch5_3[ave_r][0]<<11) | (ryg_dxt::OMatch6_3[ave_g][0]<<5) | ryg_dxt::OMatch5_3[ave_b][0];
high_color = (ryg_dxt::OMatch5_3[ave_r][1]<<11) | (ryg_dxt::OMatch6_3[ave_g][1]<<5) | ryg_dxt::OMatch5_3[ave_b][1];
improved |= evaluate_solution(dxt1_solution_coordinates((uint16)low_color, (uint16)high_color), true, &m_best_solution);
}
if (m_pParams->m_quality == cCRNDXTQualityUber)
{
// Try compressing as all-solid using the other (non-average) colors in the block in uber.
for (uint i = 0; i < m_unique_colors.size(); i++)
{
uint r = m_unique_colors[i].m_color[0];
uint g = m_unique_colors[i].m_color[1];
uint b = m_unique_colors[i].m_color[2];
if ((r == ave_r) && (g == ave_g) && (b == ave_b))
continue;
uint low_color = (ryg_dxt::OMatch5[r][0]<<11) | (ryg_dxt::OMatch6[g][0]<<5) | ryg_dxt::OMatch5[b][0];
uint high_color = (ryg_dxt::OMatch5[r][1]<<11) | (ryg_dxt::OMatch6[g][1]<<5) | ryg_dxt::OMatch5[b][1];
improved |= evaluate_solution(dxt1_solution_coordinates((uint16)low_color, (uint16)high_color), true, &m_best_solution);
if ((m_pParams->m_use_alpha_blocks) && (m_best_solution.m_error))
{
low_color = (ryg_dxt::OMatch5_3[r][0]<<11) | (ryg_dxt::OMatch6_3[g][0]<<5) | ryg_dxt::OMatch5_3[b][0];
high_color = (ryg_dxt::OMatch5_3[r][1]<<11) | (ryg_dxt::OMatch6_3[g][1]<<5) | ryg_dxt::OMatch5_3[b][1];
improved |= evaluate_solution(dxt1_solution_coordinates((uint16)low_color, (uint16)high_color), true, &m_best_solution);
}
}
}
return improved;
}
// Block is solid, trying using ryg's optimal single color tables.
bool dxt1_endpoint_optimizer::handle_solid_block()
{
int r = m_unique_colors[0].m_color.r;
int g = m_unique_colors[0].m_color.g;
int b = m_unique_colors[0].m_color.b;
//uint packed_color = dxt1_block::pack_color(r, g, b, true);
//evaluate_solution(dxt1_solution_coordinates((uint16)packed_color, (uint16)packed_color), false, &m_best_solution);
uint low_color = (ryg_dxt::OMatch5[r][0]<<11) | (ryg_dxt::OMatch6[g][0]<<5) | ryg_dxt::OMatch5[b][0];
uint high_color = (ryg_dxt::OMatch5[r][1]<<11) | (ryg_dxt::OMatch6[g][1]<<5) | ryg_dxt::OMatch5[b][1];
evaluate_solution(dxt1_solution_coordinates((uint16)low_color, (uint16)high_color), false, &m_best_solution);
if ((m_pParams->m_use_alpha_blocks) && (m_best_solution.m_error))
{
low_color = (ryg_dxt::OMatch5_3[r][0]<<11) | (ryg_dxt::OMatch6_3[g][0]<<5) | ryg_dxt::OMatch5_3[b][0];
high_color = (ryg_dxt::OMatch5_3[r][1]<<11) | (ryg_dxt::OMatch6_3[g][1]<<5) | ryg_dxt::OMatch5_3[b][1];
evaluate_solution(dxt1_solution_coordinates((uint16)low_color, (uint16)high_color), true, &m_best_solution);
}
return_solution(*m_pResults, m_best_solution);
return true;
}
void dxt1_endpoint_optimizer::compute_vectors(const vec3F& perceptual_weights)
{
m_norm_unique_colors.resize(0);
m_norm_unique_colors_weighted.resize(0);
m_mean_norm_color.clear();
m_mean_norm_color_weighted.clear();
for (uint i = 0; i < m_unique_colors.size(); i++)
{
const color_quad_u8& color = m_unique_colors[i].m_color;
const uint weight = m_unique_colors[i].m_weight;
vec3F norm_color(color.r * 1.0f/255.0f, color.g * 1.0f/255.0f, color.b * 1.0f/255.0f);
vec3F norm_color_weighted(vec3F::mul_components(perceptual_weights, norm_color));
m_norm_unique_colors.push_back(norm_color);
m_norm_unique_colors_weighted.push_back(norm_color_weighted);
m_mean_norm_color += norm_color * (float)weight;
m_mean_norm_color_weighted += norm_color_weighted * (float)weight;
}
if (m_total_unique_color_weight)
{
m_mean_norm_color *= (1.0f / m_total_unique_color_weight);
m_mean_norm_color_weighted *= (1.0f / m_total_unique_color_weight);
}
for (uint i = 0; i < m_unique_colors.size(); i++)
{
m_norm_unique_colors[i] -= m_mean_norm_color;
m_norm_unique_colors_weighted[i] -= m_mean_norm_color_weighted;
}
}
// Compute PCA (principle axis, i.e. direction of largest variance) of input vectors.
void dxt1_endpoint_optimizer::compute_pca(vec3F& axis, const vec3F_array& norm_colors, const vec3F& def)
{
#if 0
axis.clear();
CRNLIB_ASSERT(m_unique_colors.size() == norm_colors.size());
// Incremental PCA
bool first = true;
for (uint i = 0; i < norm_colors.size(); i++)
{
const uint weight = m_unique_colors[i].m_weight;
for (uint j = 0; j < weight; j++)
{
vec3F x(norm_colors[i] * norm_colors[i][0]);
vec3F y(norm_colors[i] * norm_colors[i][1]);
vec3F z(norm_colors[i] * norm_colors[i][2]);
vec3F v(first ? norm_colors[0] : axis);
first = false;
v.normalize(&def);
axis[0] += (x * v);
axis[1] += (y * v);
axis[2] += (z * v);
}
}
axis.normalize(&def);
#else
double cov[6] = { 0, 0, 0, 0, 0, 0 };
//vec3F lo(math::cNearlyInfinite);
//vec3F hi(-math::cNearlyInfinite);
for(uint i = 0; i < norm_colors.size(); i++)
{
const vec3F& v = norm_colors[i];
//if (v[0] < lo[0]) lo[0] = v[0];
//if (v[1] < lo[1]) lo[1] = v[1];
//if (v[2] < lo[2]) lo[2] = v[2];
//if (v[0] > hi[0]) hi[0] = v[0];
//if (v[1] > hi[1]) hi[1] = v[1];
//if (v[2] > hi[2]) hi[2] = v[2];
float r = v[0];
float g = v[1];
float b = v[2];
if (m_unique_colors[i].m_weight > 1)
{
const double weight = m_unique_colors[i].m_weight;
cov[0] += r*r*weight;
cov[1] += r*g*weight;
cov[2] += r*b*weight;
cov[3] += g*g*weight;
cov[4] += g*b*weight;
cov[5] += b*b*weight;
}
else
{
cov[0] += r*r;
cov[1] += r*g;
cov[2] += r*b;
cov[3] += g*g;
cov[4] += g*b;
cov[5] += b*b;
}
}
double vfr, vfg, vfb;
//vfr = hi[0] - lo[0];
//vfg = hi[1] - lo[1];
//vfb = hi[2] - lo[2];
// This is more stable.
vfr = .9f;
vfg = 1.0f;
vfb = .7f;
const uint cNumIters = 8;
for (uint iter = 0; iter < cNumIters; iter++)
{
double r = vfr*cov[0] + vfg*cov[1] + vfb*cov[2];
double g = vfr*cov[1] + vfg*cov[3] + vfb*cov[4];
double b = vfr*cov[2] + vfg*cov[4] + vfb*cov[5];
double m = math::maximum(fabs(r), fabs(g), fabs(b));
if (m > 1e-10)
{
m = 1.0f / m;
r *= m;
g *= m;
b *= m;
}
double delta = math::square(vfr-r) + math::square(vfg-g) + math::square(vfb-b);
vfr = r;
vfg = g;
vfb = b;
if ((iter > 2) && (delta < 1e-8))
break;
}
double len = vfr*vfr + vfg*vfg + vfb*vfb;
if (len < 1e-10)
{
axis = def;
}
else
{
len = 1.0f / sqrt(len);
vfr *= len;
vfg *= len;
vfb *= len;
axis.set(static_cast<float>(vfr), static_cast<float>(vfg), static_cast<float>(vfb));
}
#endif
}
static const uint8 g_invTableNull[4] = { 0, 1, 2, 3 };
static const uint8 g_invTableAlpha[4] = { 1, 0, 2, 3 };
static const uint8 g_invTableColor[4] = { 1, 0, 3, 2 };
// Computes a valid (encodable) DXT1 solution (low/high colors, swizzled selectors) from input.
void dxt1_endpoint_optimizer::return_solution(results& res, const potential_solution& solution)
{
bool invert_selectors;
if (solution.m_alpha_block)
invert_selectors = (solution.m_coords.m_low_color > solution.m_coords.m_high_color);
else
{
CRNLIB_ASSERT(solution.m_coords.m_low_color != solution.m_coords.m_high_color);
invert_selectors = (solution.m_coords.m_low_color < solution.m_coords.m_high_color);
}
if (invert_selectors)
{
res.m_low_color = solution.m_coords.m_high_color;
res.m_high_color = solution.m_coords.m_low_color;
}
else
{
res.m_low_color = solution.m_coords.m_low_color;
res.m_high_color = solution.m_coords.m_high_color;
}
const uint8* pInvert_table = g_invTableNull;
if (invert_selectors)
pInvert_table = solution.m_alpha_block ? g_invTableAlpha : g_invTableColor;
const uint alpha_thresh = m_pParams->m_pixels_have_alpha ? (m_pParams->m_dxt1a_alpha_threshold << 24U) : 0;
const uint32* pSrc_pixels = reinterpret_cast<const uint32*>(m_pParams->m_pPixels);
uint8* pDst_selectors = res.m_pSelectors;
if ((m_unique_colors.size() == 1) && (!m_pParams->m_pixels_have_alpha))
{
uint32 c = utils::read_le32(pSrc_pixels);
CRNLIB_ASSERT(c >= alpha_thresh);
c |= 0xFF000000U;
unique_color_hash_map::const_iterator it(m_unique_color_hash_map.find(c));
CRNLIB_ASSERT(it != m_unique_color_hash_map.end());
uint unique_color_index = it->second;
uint selector = pInvert_table[solution.m_selectors[unique_color_index]];
memset(pDst_selectors, selector, m_pParams->m_num_pixels);
}
else
{
uint8* pDst_selectors_end = pDst_selectors + m_pParams->m_num_pixels;
uint8 prev_selector = 0;
uint32 prev_color = 0;
do
{
uint32 c = utils::read_le32(pSrc_pixels);
pSrc_pixels++;
uint8 selector = 3;
if (c >= alpha_thresh)
{
c |= 0xFF000000U;
if (c == prev_color)
selector = prev_selector;
else
{
unique_color_hash_map::const_iterator it(m_unique_color_hash_map.find(c));
CRNLIB_ASSERT(it != m_unique_color_hash_map.end());
uint unique_color_index = it->second;
selector = pInvert_table[solution.m_selectors[unique_color_index]];
prev_color = c;
prev_selector = selector;
}
}
*pDst_selectors++ = selector;
} while (pDst_selectors != pDst_selectors_end);
}
res.m_alpha_block = solution.m_alpha_block;
res.m_error = solution.m_error;
}
inline vec3F dxt1_endpoint_optimizer::unpack_to_vec3F(uint16 packed_color)
{
color_quad_u8 c(dxt1_block::unpack_color(packed_color, false));
return vec3F(c.r * 1.0f/31.0f, c.g * 1.0f/63.0f, c.b * 1.0f/31.0f);
}
inline vec3F dxt1_endpoint_optimizer::unpack_to_vec3F_raw(uint16 packed_color)
{
color_quad_u8 c(dxt1_block::unpack_color(packed_color, false));
return vec3F(c.r, c.g, c.b);
}
// Per-component 1D endpoint optimization.
void dxt1_endpoint_optimizer::optimize_endpoint_comps()
{
if ((m_best_solution.m_alpha_block) || (!m_best_solution.m_error))
return;
//color_quad_u8 orig_l(dxt1_block::unpack_color(m_best_solution.m_coords.m_low_color, false));
//color_quad_u8 orig_h(dxt1_block::unpack_color(m_best_solution.m_coords.m_high_color, false));
//uint orig_error = m_best_solution.m_error;
color_quad_u8 orig_l_scaled(dxt1_block::unpack_color(m_best_solution.m_coords.m_low_color, true));
color_quad_u8 orig_h_scaled(dxt1_block::unpack_color(m_best_solution.m_coords.m_high_color, true));
color_quad_u8 min_color(0xFF, 0xFF, 0xFF, 0xFF);
color_quad_u8 max_color(0, 0, 0, 0);
for (uint i = 0; i < m_unique_colors.size(); i++)
{
min_color = color_quad_u8::component_min(min_color, m_unique_colors[i].m_color);
max_color = color_quad_u8::component_max(max_color, m_unique_colors[i].m_color);
}
// Try to separately optimize each component. This is a 1D problem so it's easy to compute accurate per-component error bounds.
for (uint comp_index = 0; comp_index < 3; comp_index++)
{
uint ll[4];
ll[0] = orig_l_scaled[comp_index];
ll[1] = orig_h_scaled[comp_index];
ll[2] = (ll[0]*2+ll[1])/3;
ll[3] = (ll[0]+ll[1]*2)/3;
uint error_to_beat = 0;
uint min_color_weight = 0;
uint max_color_weight = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
{
uint c = m_unique_colors[i].m_color[comp_index];
uint w = m_unique_colors[i].m_weight;
int delta = ll[m_best_solution.m_selectors[i]] - c;
error_to_beat += (int)w * (delta * delta);
if (c == min_color[comp_index])
min_color_weight += w;
if (c == max_color[comp_index])
max_color_weight += w;
}
if (!error_to_beat)
continue;
CRNLIB_ASSERT((min_color_weight > 0) && (max_color_weight > 0));
const uint error_to_beat_div_min_color_weight = min_color_weight ? ((error_to_beat + min_color_weight - 1) / min_color_weight) : 0;
const uint error_to_beat_div_max_color_weight = max_color_weight ? ((error_to_beat + max_color_weight - 1) / max_color_weight) : 0;
const uint m = (comp_index == 1) ? 63 : 31;
const uint m_shift = (comp_index == 1) ? 3 : 2;
for (uint o = 0; o <= m; o++)
{
uint tl[4];
tl[0] = (comp_index == 1) ? ((o << 2) | (o >> 4)) : ((o << 3) | (o >> 2));
for (uint h = 0; h < 8; h++)
{
const uint pl = h << m_shift;
const uint ph = ((h + 1) << m_shift) - 1;
uint tl_l = (comp_index == 1) ? ((pl << 2) | (pl >> 4)) : ((pl << 3) | (pl >> 2));
uint tl_h = (comp_index == 1) ? ((ph << 2) | (ph >> 4)) : ((ph << 3) | (ph >> 2));
tl_l = math::minimum(tl_l, tl[0]);
tl_h = math::maximum(tl_h, tl[0]);
uint c_l = min_color[comp_index];
uint c_h = max_color[comp_index];
if (c_h < tl_l)
{
uint min_possible_error = math::square<int>(tl_l - c_l);
if (min_possible_error > error_to_beat_div_min_color_weight)
continue;
}
else if (c_l > tl_h)
{
uint min_possible_error = math::square<int>(c_h - tl_h);
if (min_possible_error > error_to_beat_div_max_color_weight)
continue;
}
for (uint p = pl; p <= ph; p++)
{
tl[1] = (comp_index == 1) ? ((p << 2) | (p >> 4)) : ((p << 3) | (p >> 2));
tl[2] = (tl[0]*2+tl[1])/3;
tl[3] = (tl[0]+tl[1]*2)/3;
uint trial_error = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
{
int delta = tl[m_best_solution.m_selectors[i]] - m_unique_colors[i].m_color[comp_index];
trial_error += m_unique_colors[i].m_weight * (delta * delta);
if (trial_error >= error_to_beat)
break;
}
//CRNLIB_ASSERT(trial_error >= min_possible_error);
if (trial_error < error_to_beat)
{
color_quad_u8 l(dxt1_block::unpack_color(m_best_solution.m_coords.m_low_color, false));
color_quad_u8 h(dxt1_block::unpack_color(m_best_solution.m_coords.m_high_color, false));
l[comp_index] = static_cast<uint8>(o);
h[comp_index] = static_cast<uint8>(p);
bool better = evaluate_solution(
dxt1_solution_coordinates(dxt1_block::pack_color(l, false), dxt1_block::pack_color(h, false)),
true, &m_best_solution);
better;
if (better)
{
#if 0
printf("comp: %u, orig: %u %u, new: %u %u, orig_error: %u, new_error: %u\n", comp_index,
orig_l[comp_index], orig_h[comp_index],
l[comp_index], h[comp_index],
orig_error, m_best_solution.m_error);
#endif
if (!m_best_solution.m_error)
return;
error_to_beat = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
{
int delta = tl[m_best_solution.m_selectors[i]] - m_unique_colors[i].m_color[comp_index];
error_to_beat += m_unique_colors[i].m_weight * (delta * delta);
}
} // better
//goto early_out;
} // if (trial_error < error_to_beat)
} // for (uint p = 0; p <= m; p++)
}
} // for (uint o = 0; o <= m; o++)
} // comp_index
}
// Voxel adjacency delta coordinations.
static const struct adjacent_coords
{
int8 x, y, z;
} g_adjacency[26] = {
{-1, -1, -1},
{0, -1, -1},
{1, -1, -1},
{-1, 0, -1},
{0, 0, -1},
{1, 0, -1},
{-1, 1, -1},
{0, 1, -1},
{1, 1, -1},
{-1, -1, 0},
{0, -1, 0},
{1, -1, 0},
{-1, 0, 0},
{1, 0, 0},
{-1, 1, 0},
{0, 1, 0},
{1, 1, 0},
{-1, -1, 1},
{0, -1, 1},
{1, -1, 1},
{-1, 0, 1},
{0, 0, 1},
{1, 0, 1},
{-1, 1, 1},
{0, 1, 1},
{1, 1, 1}
};
// Attempt to refine current solution's endpoints given the current selectors using least squares.
bool dxt1_endpoint_optimizer::refine_solution(int refinement_level)
{
CRNLIB_ASSERT(m_best_solution.m_valid);
static const int w1Tab[4] = { 3,0,2,1 };
static const int prods_0[4] = { 0x00,0x00,0x02,0x02 };
static const int prods_1[4] = { 0x00,0x09,0x01,0x04 };
static const int prods_2[4] = { 0x09,0x00,0x04,0x01 };
double akku_0 = 0;
double akku_1 = 0;
double akku_2 = 0;
double At1_r, At1_g, At1_b;
double At2_r, At2_g, At2_b;
At1_r = At1_g = At1_b = 0;
At2_r = At2_g = At2_b = 0;
for(uint i = 0; i < m_unique_colors.size(); i++)
{
const color_quad_u8& c = m_unique_colors[i].m_color;
const double weight = m_unique_colors[i].m_weight;
double r = c.r*weight;
double g = c.g*weight;
double b = c.b*weight;
int step = m_best_solution.m_selectors[i]^1;
int w1 = w1Tab[step];
akku_0 += prods_0[step]*weight;
akku_1 += prods_1[step]*weight;
akku_2 += prods_2[step]*weight;
At1_r += w1*r;
At1_g += w1*g;
At1_b += w1*b;
At2_r += r;
At2_g += g;
At2_b += b;
}
At2_r = 3*At2_r - At1_r;
At2_g = 3*At2_g - At1_g;
At2_b = 3*At2_b - At1_b;
double xx = akku_2;
double yy = akku_1;
double xy = akku_0;
double t = xx * yy - xy * xy;
if (!yy || !xx || (fabs(t) < .0000125f))
return false;
double frb = (3.0f * 31.0f / 255.0f) / t;
double fg = frb * (63.0f / 31.0f);
bool improved = false;
if (refinement_level == 0)
{
uint max16;
max16 = math::clamp<int>(static_cast<int>((At1_r*yy - At2_r*xy)*frb+0.5f),0,31) << 11;
max16 |= math::clamp<int>(static_cast<int>((At1_g*yy - At2_g*xy)*fg +0.5f),0,63) << 5;
max16 |= math::clamp<int>(static_cast<int>((At1_b*yy - At2_b*xy)*frb+0.5f),0,31) << 0;
uint min16;
min16 = math::clamp<int>(static_cast<int>((At2_r*xx - At1_r*xy)*frb+0.5f),0,31) << 11;
min16 |= math::clamp<int>(static_cast<int>((At2_g*xx - At1_g*xy)*fg +0.5f),0,63) << 5;
min16 |= math::clamp<int>(static_cast<int>((At2_b*xx - At1_b*xy)*frb+0.5f),0,31) << 0;
dxt1_solution_coordinates nc((uint16)min16, (uint16)max16);
nc.canonicalize();
improved |= evaluate_solution(nc, true, &m_best_solution, false);
}
else if (refinement_level == 1)
{
// Try exploring the local lattice neighbors of the least squares optimized result.
color_quad_u8 e[2];
e[0].clear();
e[0][0] = (uint8)math::clamp<int>(static_cast<int>((At1_r*yy - At2_r*xy)*frb+0.5f),0,31);
e[0][1] = (uint8)math::clamp<int>(static_cast<int>((At1_g*yy - At2_g*xy)*fg +0.5f),0,63);
e[0][2] = (uint8)math::clamp<int>(static_cast<int>((At1_b*yy - At2_b*xy)*frb+0.5f),0,31);
e[1].clear();
e[1][0] = (uint8)math::clamp<int>(static_cast<int>((At2_r*xx - At1_r*xy)*frb+0.5f),0,31);
e[1][1] = (uint8)math::clamp<int>(static_cast<int>((At2_g*xx - At1_g*xy)*fg +0.5f),0,63);
e[1][2] = (uint8)math::clamp<int>(static_cast<int>((At2_b*xx - At1_b*xy)*frb+0.5f),0,31);
for (uint i = 0; i < 2; i++)
{
for (int rr = -1; rr <= 1; rr++)
{
for (int gr = -1; gr <= 1; gr++)
{
for (int br = -1; br <= 1; br++)
{
dxt1_solution_coordinates nc;
color_quad_u8 c[2];
c[0] = e[0];
c[1] = e[1];
c[i][0] = (uint8)math::clamp<int>(c[i][0] + rr, 0, 31);
c[i][1] = (uint8)math::clamp<int>(c[i][1] + gr, 0, 63);
c[i][2] = (uint8)math::clamp<int>(c[i][2] + br, 0, 31);
nc.m_low_color = dxt1_block::pack_color(c[0], false);
nc.m_high_color = dxt1_block::pack_color(c[1], false);
nc.canonicalize();
if ((nc.m_low_color != m_best_solution.m_coords.m_low_color) || (nc.m_high_color != m_best_solution.m_coords.m_high_color))
{
improved |= evaluate_solution(nc, true, &m_best_solution, false);
}
}
}
}
}
}
else
{
// Try even harder to explore the local lattice neighbors of the least squares optimized result.
color_quad_u8 e[2];
e[0].clear();
e[0][0] = (uint8)math::clamp<int>(static_cast<int>((At1_r*yy - At2_r*xy)*frb+0.5f),0,31);
e[0][1] = (uint8)math::clamp<int>(static_cast<int>((At1_g*yy - At2_g*xy)*fg +0.5f),0,63);
e[0][2] = (uint8)math::clamp<int>(static_cast<int>((At1_b*yy - At2_b*xy)*frb+0.5f),0,31);
e[1].clear();
e[1][0] = (uint8)math::clamp<int>(static_cast<int>((At2_r*xx - At1_r*xy)*frb+0.5f),0,31);
e[1][1] = (uint8)math::clamp<int>(static_cast<int>((At2_g*xx - At1_g*xy)*fg +0.5f),0,63);
e[1][2] = (uint8)math::clamp<int>(static_cast<int>((At2_b*xx - At1_b*xy)*frb+0.5f),0,31);
for (int orr = -1; orr <= 1; orr++)
{
for (int ogr = -1; ogr <= 1; ogr++)
{
for (int obr = -1; obr <= 1; obr++)
{
dxt1_solution_coordinates nc;
color_quad_u8 c[2];
c[0] = e[0];
c[1] = e[1];
c[0][0] = (uint8)math::clamp<int>(c[0][0] + orr, 0, 31);
c[0][1] = (uint8)math::clamp<int>(c[0][1] + ogr, 0, 63);
c[0][2] = (uint8)math::clamp<int>(c[0][2] + obr, 0, 31);
for (int rr = -1; rr <= 1; rr++)
{
for (int gr = -1; gr <= 1; gr++)
{
for (int br = -1; br <= 1; br++)
{
c[1][0] = (uint8)math::clamp<int>(c[1][0] + rr, 0, 31);
c[1][1] = (uint8)math::clamp<int>(c[1][1] + gr, 0, 63);
c[1][2] = (uint8)math::clamp<int>(c[1][2] + br, 0, 31);
nc.m_low_color = dxt1_block::pack_color(c[0], false);
nc.m_high_color = dxt1_block::pack_color(c[1], false);
nc.canonicalize();
improved |= evaluate_solution(nc, true, &m_best_solution, false);
}
}
}
}
}
}
}
return improved;
}
//-----------------------------------------------------------------------------------------------------------------------------------------
// Primary endpoint optimization entrypoint.
bool dxt1_endpoint_optimizer::optimize_endpoints(vec3F& low_color, vec3F& high_color)
{
vec3F orig_low_color(low_color);
vec3F orig_high_color(high_color);
m_trial_solution.clear();
uint num_passes;
const int16* pProbe_table = g_uber_probe_table;
uint probe_range;
float dist_per_trial = .015625f;
// How many probes, and the distance between each probe depends on the quality level.
switch (m_pParams->m_quality)
{
case cCRNDXTQualitySuperFast:
pProbe_table = g_fast_probe_table;
probe_range = cFastProbeTableSize;
dist_per_trial = .027063293f;
num_passes = 1;
break;
case cCRNDXTQualityFast:
pProbe_table = g_fast_probe_table;
probe_range = cFastProbeTableSize;
dist_per_trial = .027063293f;
num_passes = 2;
break;
case cCRNDXTQualityNormal:
pProbe_table = g_normal_probe_table;
probe_range = cNormalProbeTableSize;
dist_per_trial = .027063293f;
num_passes = 2;
break;
case cCRNDXTQualityBetter:
pProbe_table = g_better_probe_table;
probe_range = cBetterProbeTableSize;
num_passes = 2;
break;
default:
pProbe_table = g_uber_probe_table;
probe_range = cUberProbeTableSize;
num_passes = 4;
break;
}
m_solutions_tried.reset();
if (m_pParams->m_endpoint_caching)
{
// Try the previous X winning endpoints. This may not give us optimal results, but it may increase the probability of early outs while evaluating potential solutions.
const uint num_prev_results = math::minimum<uint>(cMaxPrevResults, m_num_prev_results);
for (uint i = 0; i < num_prev_results; i++)
{
const dxt1_solution_coordinates& coords = m_prev_results[i];
solution_hash_map::insert_result solution_res(m_solutions_tried.insert(coords.m_low_color | (coords.m_high_color << 16U)));
if (!solution_res.second)
continue;
evaluate_solution(coords, true, &m_best_solution);
}
if (!m_best_solution.m_error)
{
// Got lucky - one of the previous endpoints is optimal.
return_solution(*m_pResults, m_best_solution);
return true;
}
}
if (m_pParams->m_quality >= cCRNDXTQualityBetter)
{
//evaluate_solution(dxt1_solution_coordinates(low_color, high_color), true, &m_best_solution);
//refine_solution();
try_median4(orig_low_color, orig_high_color);
}
uint probe_low[cUberProbeTableSize * 2 + 1];
uint probe_high[cUberProbeTableSize * 2 + 1];
vec3F scaled_principle_axis[2];
scaled_principle_axis[1] = m_principle_axis * dist_per_trial;
scaled_principle_axis[1][0] *= 31.0f;
scaled_principle_axis[1][1] *= 63.0f;
scaled_principle_axis[1][2] *= 31.0f;
scaled_principle_axis[0] = -scaled_principle_axis[1];
//vec3F initial_ofs(scaled_principle_axis * (float)-probe_range);
//initial_ofs[0] += .5f;
//initial_ofs[1] += .5f;
//initial_ofs[2] += .5f;
low_color[0] = math::clamp(low_color[0] * 31.0f, 0.0f, 31.0f);
low_color[1] = math::clamp(low_color[1] * 63.0f, 0.0f, 63.0f);
low_color[2] = math::clamp(low_color[2] * 31.0f, 0.0f, 31.0f);
high_color[0] = math::clamp(high_color[0] * 31.0f, 0.0f, 31.0f);
high_color[1] = math::clamp(high_color[1] * 63.0f, 0.0f, 63.0f);
high_color[2] = math::clamp(high_color[2] * 31.0f, 0.0f, 31.0f);
for (uint pass = 0; pass < num_passes; pass++)
{
// Now separately sweep or probe the low and high colors along the principle axis, both positively and negatively.
// This results in two arrays of candidate low/high endpoints. Every unique combination of candidate endpoints is tried as a potential solution.
// In higher quality modes, the various nearby lattice neighbors of each candidate endpoint are also explored, which allows the current solution to "wobble" or "migrate"
// to areas with lower error.
// This entire process can be repeated up to X times (depending on the quality level) until a local minimum is established.
// This method is very stable and scalable. It could be implemented more elegantly, but I'm now very cautious of touching this code.
if (pass)
{
low_color = unpack_to_vec3F_raw(m_best_solution.m_coords.m_low_color);
high_color = unpack_to_vec3F_raw(m_best_solution.m_coords.m_high_color);
}
const uint64 prev_best_error = m_best_solution.m_error;
if (!prev_best_error)
break;
// Sweep low endpoint along principle axis, record positions
int prev_packed_color[2] = { -1, -1 };
uint num_low_trials = 0;
vec3F initial_probe_low_color(low_color + vec3F(.5f));
for (uint i = 0; i < probe_range; i++)
{
const int ls = i ? 0 : 1;
int x = pProbe_table[i];
for (int s = ls; s < 2; s++)
{
vec3F probe_low_color(initial_probe_low_color + scaled_principle_axis[s] * (float)x);
int r = math::clamp((int)floor(probe_low_color[0]), 0, 31);
int g = math::clamp((int)floor(probe_low_color[1]), 0, 63);
int b = math::clamp((int)floor(probe_low_color[2]), 0, 31);
int packed_color = b | (g << 5U) | (r << 11U);
if (packed_color != prev_packed_color[s])
{
probe_low[num_low_trials++] = packed_color;
prev_packed_color[s] = packed_color;
}
}
}
prev_packed_color[0] = -1;
prev_packed_color[1] = -1;
// Sweep high endpoint along principle axis, record positions
uint num_high_trials = 0;
vec3F initial_probe_high_color(high_color + vec3F(.5f));
for (uint i = 0; i < probe_range; i++)
{
const int ls = i ? 0 : 1;
int x = pProbe_table[i];
for (int s = ls; s < 2; s++)
{
vec3F probe_high_color(initial_probe_high_color + scaled_principle_axis[s] * (float)x);
int r = math::clamp((int)floor(probe_high_color[0]), 0, 31);
int g = math::clamp((int)floor(probe_high_color[1]), 0, 63);
int b = math::clamp((int)floor(probe_high_color[2]), 0, 31);
int packed_color = b | (g << 5U) | (r << 11U);
if (packed_color != prev_packed_color[s])
{
probe_high[num_high_trials++] = packed_color;
prev_packed_color[s] = packed_color;
}
}
}
// Now try all unique combinations.
for (uint i = 0; i < num_low_trials; i++)
{
for (uint j = 0; j < num_high_trials; j++)
{
dxt1_solution_coordinates coords((uint16)probe_low[i], (uint16)probe_high[j]);
coords.canonicalize();
solution_hash_map::insert_result solution_res(m_solutions_tried.insert(coords.m_low_color | (coords.m_high_color << 16U)));
if (!solution_res.second)
continue;
evaluate_solution(coords, true, &m_best_solution);
}
}
if (m_pParams->m_quality >= cCRNDXTQualityNormal)
{
// Generate new candidates by exploring the low color's direct lattice neighbors
color_quad_u8 lc(dxt1_block::unpack_color(m_best_solution.m_coords.m_low_color, false));
for (int i = 0; i < 26; i++)
{
int r = lc.r + g_adjacency[i].x;
if ((r < 0) || (r > 31)) continue;
int g = lc.g + g_adjacency[i].y;
if ((g < 0) || (g > 63)) continue;
int b = lc.b + g_adjacency[i].z;
if ((b < 0) || (b > 31)) continue;
dxt1_solution_coordinates coords(dxt1_block::pack_color(r, g, b, false), m_best_solution.m_coords.m_high_color);
coords.canonicalize();
solution_hash_map::insert_result solution_res(m_solutions_tried.insert(coords.m_low_color | (coords.m_high_color << 16U)));
if (solution_res.second)
evaluate_solution(coords, true, &m_best_solution);
}
if (m_pParams->m_quality == cCRNDXTQualityUber)
{
// Generate new candidates by exploring the low color's direct lattice neighbors - this time, explore much further separately on each axis.
lc = dxt1_block::unpack_color(m_best_solution.m_coords.m_low_color, false);
for (int a = 0; a < 3; a++)
{
int limit = (a == 1) ? 63 : 31;
for (int s = -2; s <= 2; s += 4)
{
color_quad_u8 c(lc);
int q = c[a] + s;
if ((q < 0) || (q > limit)) continue;
c[a] = (uint8)q;
dxt1_solution_coordinates coords(dxt1_block::pack_color(c, false), m_best_solution.m_coords.m_high_color);
coords.canonicalize();
solution_hash_map::insert_result solution_res(m_solutions_tried.insert(coords.m_low_color | (coords.m_high_color << 16U)));
if (solution_res.second)
evaluate_solution(coords, true, &m_best_solution);
}
}
}
// Generate new candidates by exploring the high color's direct lattice neighbors
color_quad_u8 hc(dxt1_block::unpack_color(m_best_solution.m_coords.m_high_color, false));
for (int i = 0; i < 26; i++)
{
int r = hc.r + g_adjacency[i].x;
if ((r < 0) || (r > 31)) continue;
int g = hc.g + g_adjacency[i].y;
if ((g < 0) || (g > 63)) continue;
int b = hc.b + g_adjacency[i].z;
if ((b < 0) || (b > 31)) continue;
dxt1_solution_coordinates coords(m_best_solution.m_coords.m_low_color, dxt1_block::pack_color(r, g, b, false));
coords.canonicalize();
solution_hash_map::insert_result solution_res(m_solutions_tried.insert(coords.m_low_color | (coords.m_high_color << 16U)));
if (solution_res.second)
evaluate_solution(coords, true, &m_best_solution);
}
if (m_pParams->m_quality == cCRNDXTQualityUber)
{
// Generate new candidates by exploring the high color's direct lattice neighbors - this time, explore much further separately on each axis.
hc = dxt1_block::unpack_color(m_best_solution.m_coords.m_high_color, false);
for (int a = 0; a < 3; a++)
{
int limit = (a == 1) ? 63 : 31;
for (int s = -2; s <= 2; s += 4)
{
color_quad_u8 c(hc);
int q = c[a] + s;
if ((q < 0) || (q > limit)) continue;
c[a] = (uint8)q;
dxt1_solution_coordinates coords(m_best_solution.m_coords.m_low_color, dxt1_block::pack_color(c, false));
coords.canonicalize();
solution_hash_map::insert_result solution_res(m_solutions_tried.insert(coords.m_low_color | (coords.m_high_color << 16U)));
if (solution_res.second)
evaluate_solution(coords, true, &m_best_solution);
}
}
}
}
if ((!m_best_solution.m_error) || ((pass) && (m_best_solution.m_error == prev_best_error)))
break;
if (m_pParams->m_quality >= cCRNDXTQualityUber)
{
// Attempt to refine current solution's endpoints given the current selectors using least squares.
refine_solution(1);
}
}
if (m_pParams->m_quality >= cCRNDXTQualityNormal)
{
if ((m_best_solution.m_error) && (!m_pParams->m_pixels_have_alpha))
{
bool choose_solid_block = false;
if (m_best_solution.are_selectors_all_equal())
{
// All selectors equal - try various solid-block optimizations
choose_solid_block = try_average_block_as_solid();
}
if ((!choose_solid_block) && (m_pParams->m_quality == cCRNDXTQualityUber))
{
// Per-component 1D endpoint optimization.
optimize_endpoint_comps();
}
}
if (m_pParams->m_quality == cCRNDXTQualityUber)
{
if (m_best_solution.m_error)
{
// The pixels may have already been DXTc compressed by another compressor.
// It's usually possible to recover the endpoints used to previously pack the block.
try_combinatorial_encoding();
}
}
}
return_solution(*m_pResults, m_best_solution);
if (m_pParams->m_endpoint_caching)
{
// Remember result for later reruse.
m_prev_results[m_num_prev_results & (cMaxPrevResults - 1)] = m_best_solution.m_coords;
m_num_prev_results++;
}
return true;
}
static inline int mul_8bit(int a, int b)
{
int t = a * b + 128;
return (t + (t >> 8)) >> 8;
}
bool dxt1_endpoint_optimizer::handle_multicolor_block()
{
uint num_passes = 1;
vec3F perceptual_weights(1.0f);
if (m_perceptual)
{
// Compute RGB weighting for use in perceptual mode.
// The more saturated the block, the more the weights deviate from (1,1,1).
float ave_redness = 0;
float ave_blueness = 0;
float ave_l = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
{
const color_quad_u8& c = m_unique_colors[i].m_color;
const float weight = (float)m_unique_colors[i].m_weight;
int l = mul_8bit(c.r + c.g + c.b, 0x55); // /3
ave_l += l;
l = math::maximum(1, l);
float scale = weight / static_cast<float>(l);
ave_redness += scale * c.r;
ave_blueness += scale * c.b;
}
ave_redness /= m_total_unique_color_weight;
ave_blueness /= m_total_unique_color_weight;
ave_l /= m_total_unique_color_weight;
ave_l = math::minimum(1.0f, ave_l * 16.0f / 255.0f);
//float r = ave_l * powf(math::saturate(ave_redness / 3.0f), 5.0f);
//float b = ave_l * powf(math::saturate(ave_blueness / 3.0f), 5.0f);
float p = ave_l * powf(math::saturate(math::maximum(ave_redness, ave_blueness) * 1.0f/3.0f), 2.75f);
if (p >= 1.0f)
num_passes = 1;
else
{
num_passes = 2;
perceptual_weights = vec3F::lerp(vec3F(.212f, .72f, .072f), perceptual_weights, p);
}
}
for (uint pass_index = 0; pass_index < num_passes; pass_index++)
{
compute_vectors(perceptual_weights);
compute_pca(m_principle_axis, m_norm_unique_colors_weighted, vec3F(.2837149f, 0.9540631f, 0.096277453f));
#if 0
matrix44F m(matrix44F::make_scale_matrix(perceptual_weights[0], perceptual_weights[1], perceptual_weights[2]));
matrix44F im(m.get_inverse());
im.transpose_in_place();
m_principle_axis = m_principle_axis * im;
#else
// Purposely scale the components of the principle axis by the perceptual weighting.
// There's probably a cleaner way to go about this, but it works (more competitive in perceptual mode against nvdxt.exe or ATI_Compress).
m_principle_axis[0] /= perceptual_weights[0];
m_principle_axis[1] /= perceptual_weights[1];
m_principle_axis[2] /= perceptual_weights[2];
#endif
m_principle_axis.normalize_in_place();
if (num_passes > 1)
{
// Check for obviously wild principle axes and try to compensate by backing off the component weightings.
if (fabs(m_principle_axis[0]) >= .795f)
perceptual_weights.set(.424f, .6f, .072f);
else if (fabs(m_principle_axis[2]) >= .795f)
perceptual_weights.set(.212f, .6f, .212f);
else
break;
}
}
// Find bounds of projection onto (potentially skewed) principle axis.
float l = 1e+9;
float h = -1e+9;
for (uint i = 0; i < m_norm_unique_colors.size(); i++)
{
float d = m_norm_unique_colors[i] * m_principle_axis;
l = math::minimum(l, d);
h = math::maximum(h, d);
}
vec3F low_color(m_mean_norm_color + l * m_principle_axis);
vec3F high_color(m_mean_norm_color + h * m_principle_axis);
if (!low_color.is_within_bounds(0.0f, 1.0f))
{
// Low color is outside the lattice, so bring it back in by casting a ray.
vec3F coord;
float t;
aabb3F bounds(vec3F(0.0f), vec3F(1.0f));
intersection::result res = intersection::ray_aabb(coord, t, ray3F(low_color, m_principle_axis), bounds);
if (res == intersection::cSuccess)
low_color = coord;
}
if (!high_color.is_within_bounds(0.0f, 1.0f))
{
// High color is outside the lattice, so bring it back in by casting a ray.
vec3F coord;
float t;
aabb3F bounds(vec3F(0.0f), vec3F(1.0f));
intersection::result res = intersection::ray_aabb(coord, t, ray3F(high_color, -m_principle_axis), bounds);
if (res == intersection::cSuccess)
high_color = coord;
}
// Now optimize the endpoints using the projection bounds on the (potentially skewed) principle axis as a starting point.
if (!optimize_endpoints(low_color, high_color))
return false;
return true;
}
bool dxt1_endpoint_optimizer::handle_grayscale_block()
{
// TODO
return true;
}
// Tries quantizing the block to 4 colors using vanilla LBG. It tries all combinations of the quantized results as potential endpoints.
bool dxt1_endpoint_optimizer::try_median4(const vec3F& low_color, const vec3F& high_color)
{
vec3F means[4];
if (m_unique_colors.size() <= 4)
{
for (uint i = 0; i < 4; i++)
means[i] = m_norm_unique_colors[math::minimum<int>(m_norm_unique_colors.size() - 1, i)];
}
else
{
means[0] = low_color - m_mean_norm_color;
means[3] = high_color - m_mean_norm_color;
means[1] = vec3F::lerp(means[0], means[3], 1.0f/3.0f);
means[2] = vec3F::lerp(means[0], means[3], 2.0f/3.0f);
fast_random rm;
const uint cMaxIters = 8;
uint reassign_rover = 0;
float prev_total_dist = math::cNearlyInfinite;
for (uint iter = 0; iter < cMaxIters; iter++)
{
vec3F new_means[4];
float new_weights[4];
utils::zero_object(new_means);
utils::zero_object(new_weights);
float total_dist = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
{
const vec3F& v = m_norm_unique_colors[i];
float best_dist = means[0].squared_distance(v);
int best_index = 0;
for (uint j = 1; j < 4; j++)
{
float dist = means[j].squared_distance(v);
if (dist < best_dist)
{
best_dist = dist;
best_index = j;
}
}
total_dist += best_dist;
new_means[best_index] += v * (float)m_unique_colors[i].m_weight;
new_weights[best_index] += (float)m_unique_colors[i].m_weight;
}
uint highest_index = 0;
float highest_weight = 0;
bool empty_cell = false;
for (uint j = 0; j < 4; j++)
{
if (new_weights[j] > 0.0f)
{
means[j] = new_means[j] / new_weights[j];
if (new_weights[j] > highest_weight)
{
highest_weight = new_weights[j];
highest_index = j;
}
}
else
empty_cell = true;
}
if (!empty_cell)
{
if (fabs(total_dist - prev_total_dist) < .00001f)
break;
prev_total_dist = total_dist;
}
else
prev_total_dist = math::cNearlyInfinite;
if ((empty_cell) && (iter != (cMaxIters - 1)))
{
const uint ri = (highest_index + reassign_rover) & 3;
reassign_rover++;
for (uint j = 0; j < 4; j++)
{
if (new_weights[j] == 0.0f)
{
means[j] = means[ri];
means[j] += vec3F::make_random(rm, -.00196f, .00196f);
}
}
}
}
}
bool improved = false;
for (uint i = 0; i < 3; i++)
{
for (uint j = i + 1; j < 4; j++)
{
const vec3F v0(means[i] + m_mean_norm_color);
const vec3F v1(means[j] + m_mean_norm_color);
dxt1_solution_coordinates sc(
color_quad_u8((int)floor(.5f + v0[0] * 31.0f), (int)floor(.5f + v0[1] * 63.0f), (int)floor(.5f + v0[2] * 31.0f), 255),
color_quad_u8((int)floor(.5f + v1[0] * 31.0f), (int)floor(.5f + v1[1] * 63.0f), (int)floor(.5f + v1[2] * 31.0f), 255), false );
sc.canonicalize();
improved |= evaluate_solution(sc, true, &m_best_solution, false);
}
}
improved |= refine_solution((m_pParams->m_quality == cCRNDXTQualityUber) ? 1 : 0);
return improved;
}
// Given candidate low/high endpoints, find the optimal selectors for 3 and 4 color blocks, compute the resulting error,
// and use the candidate if it results in less error than the best found result so far.
bool dxt1_endpoint_optimizer::evaluate_solution(
const dxt1_solution_coordinates& coords,
bool early_out,
potential_solution* pBest_solution,
bool alternate_rounding)
{
m_total_evals++;
if ((!m_pSolutions) || (alternate_rounding))
{
if (m_pParams->m_quality >= cCRNDXTQualityBetter)
return evaluate_solution_uber(m_trial_solution, coords, early_out, pBest_solution, alternate_rounding);
else
return evaluate_solution_fast(m_trial_solution, coords, early_out, pBest_solution, alternate_rounding);
}
evaluate_solution_uber(m_trial_solution, coords, false, NULL, alternate_rounding);
CRNLIB_ASSERT(m_trial_solution.m_valid);
// Caller has requested all considered candidate solutions for later analysis.
m_pSolutions->resize(m_pSolutions->size() + 1);
solution& new_solution = m_pSolutions->back();
new_solution.m_selectors.resize(m_pParams->m_num_pixels);
new_solution.m_results.m_pSelectors = &new_solution.m_selectors[0];
return_solution(new_solution.m_results, m_trial_solution);
if ((pBest_solution) && (m_trial_solution.m_error < m_best_solution.m_error))
{
*pBest_solution = m_trial_solution;
return true;
}
return false;
}
inline uint dxt1_endpoint_optimizer::color_distance(bool perceptual, const color_quad_u8& e1, const color_quad_u8& e2, bool alpha)
{
if (perceptual)
{
return color::color_distance(true, e1, e2, alpha);
}
else if (m_pParams->m_grayscale_sampling)
{
// Computes error assuming shader will be converting the result to grayscale.
int y0 = color::RGB_to_Y(e1);
int y1 = color::RGB_to_Y(e2);
int yd = y0 - y1;
if (alpha)
{
int da = (int)e1[3] - (int)e2[3];
return yd * yd + da * da;
}
else
{
return yd * yd;
}
}
else if (m_has_color_weighting)
{
// Compute error using user provided color component weights.
int dr = (int)e1[0] - (int)e2[0];
int dg = (int)e1[1] - (int)e2[1];
int db = (int)e1[2] - (int)e2[2];
dr = (dr * dr) * m_pParams->m_color_weights[0];
dg = (dg * dg) * m_pParams->m_color_weights[1];
db = (db * db) * m_pParams->m_color_weights[2];
if (alpha)
{
int da = (int)e1[3] - (int)e2[3];
da = (da * da) * (m_pParams->m_color_weights[0] + m_pParams->m_color_weights[1] + m_pParams->m_color_weights[2]);
return dr + dg + db + da;
}
else
{
return dr + dg + db;
}
}
else
{
return color::color_distance(false, e1, e2, alpha);
}
}
bool dxt1_endpoint_optimizer::evaluate_solution_uber(
potential_solution& solution,
const dxt1_solution_coordinates& coords,
bool early_out,
potential_solution* pBest_solution,
bool alternate_rounding)
{
solution.m_coords = coords;
solution.m_selectors.resize(m_unique_colors.size());
if ((pBest_solution) && (early_out))
solution.m_error = pBest_solution->m_error;
else
solution.m_error = cUINT64_MAX;
solution.m_alpha_block = false;
solution.m_valid = false;
uint first_block_type = 0;
uint last_block_type = 1;
if ((m_pParams->m_pixels_have_alpha) || (m_pParams->m_force_alpha_blocks))
first_block_type = 1;
else if (!m_pParams->m_use_alpha_blocks)
last_block_type = 0;
m_trial_selectors.resize(m_unique_colors.size());
color_quad_u8 colors[cDXT1SelectorValues];
colors[0] = dxt1_block::unpack_color(coords.m_low_color, true);
colors[1] = dxt1_block::unpack_color(coords.m_high_color, true);
for (uint block_type = first_block_type; block_type <= last_block_type; block_type++)
{
uint64 trial_error = 0;
if (!block_type)
{
colors[2].set_noclamp_rgba( (colors[0].r * 2 + colors[1].r + alternate_rounding) / 3, (colors[0].g * 2 + colors[1].g + alternate_rounding) / 3, (colors[0].b * 2 + colors[1].b + alternate_rounding) / 3, 0);
colors[3].set_noclamp_rgba( (colors[1].r * 2 + colors[0].r + alternate_rounding) / 3, (colors[1].g * 2 + colors[0].g + alternate_rounding) / 3, (colors[1].b * 2 + colors[0].b + alternate_rounding) / 3, 0);
if (m_perceptual)
{
for (int unique_color_index = (int)m_unique_colors.size() - 1; unique_color_index >= 0; unique_color_index--)
{
const color_quad_u8& c = m_unique_colors[unique_color_index].m_color;
uint best_error = color_distance(true, c, colors[0], false);
uint best_color_index = 0;
uint err = color_distance(true, c, colors[1], false);
if (err < best_error) { best_error = err; best_color_index = 1; }
err = color_distance(true, c, colors[2], false);
if (err < best_error) { best_error = err; best_color_index = 2; }
err = color_distance(true, c, colors[3], false);
if (err < best_error) { best_error = err; best_color_index = 3; }
trial_error += best_error * m_unique_colors[unique_color_index].m_weight;
if (trial_error >= solution.m_error)
break;
m_trial_selectors[unique_color_index] = static_cast<uint8>(best_color_index);
}
}
else
{
for (int unique_color_index = (int)m_unique_colors.size() - 1; unique_color_index >= 0; unique_color_index--)
{
const color_quad_u8& c = m_unique_colors[unique_color_index].m_color;
uint best_error = color_distance(false, c, colors[0], false);
uint best_color_index = 0;
uint err = color_distance(false, c, colors[1], false);
if (err < best_error) { best_error = err; best_color_index = 1; }
err = color_distance(false, c, colors[2], false);
if (err < best_error) { best_error = err; best_color_index = 2; }
err = color_distance(false, c, colors[3], false);
if (err < best_error) { best_error = err; best_color_index = 3; }
trial_error += best_error * m_unique_colors[unique_color_index].m_weight;
if (trial_error >= solution.m_error)
break;
m_trial_selectors[unique_color_index] = static_cast<uint8>(best_color_index);
}
}
}
else
{
colors[2].set_noclamp_rgba( (colors[0].r + colors[1].r + alternate_rounding) >> 1, (colors[0].g + colors[1].g + alternate_rounding) >> 1, (colors[0].b + colors[1].b + alternate_rounding) >> 1, 255U);
if (m_perceptual)
{
for (int unique_color_index = (int)m_unique_colors.size() - 1; unique_color_index >= 0; unique_color_index--)
{
const color_quad_u8& c = m_unique_colors[unique_color_index].m_color;
uint best_error = color_distance(true, c, colors[0], false);
uint best_color_index = 0;
uint err = color_distance(true, c, colors[1], false);
if (err < best_error) { best_error = err; best_color_index = 1; }
err = color_distance(true, c, colors[2], false);
if (err < best_error) { best_error = err; best_color_index = 2; }
trial_error += best_error * m_unique_colors[unique_color_index].m_weight;
if (trial_error >= solution.m_error)
break;
m_trial_selectors[unique_color_index] = static_cast<uint8>(best_color_index);
}
}
else
{
for (int unique_color_index = (int)m_unique_colors.size() - 1; unique_color_index >= 0; unique_color_index--)
{
const color_quad_u8& c = m_unique_colors[unique_color_index].m_color;
uint best_error = color_distance(false, c, colors[0], false);
uint best_color_index = 0;
uint err = color_distance(false, c, colors[1], false);
if (err < best_error) { best_error = err; best_color_index = 1; }
err = color_distance(false, c, colors[2], false);
if (err < best_error) { best_error = err; best_color_index = 2; }
trial_error += best_error * m_unique_colors[unique_color_index].m_weight;
if (trial_error >= solution.m_error)
break;
m_trial_selectors[unique_color_index] = static_cast<uint8>(best_color_index);
}
}
}
if (trial_error < solution.m_error)
{
solution.m_error = trial_error;
solution.m_alpha_block = (block_type != 0);
solution.m_selectors = m_trial_selectors;
solution.m_valid = true;
}
}
if ((!solution.m_alpha_block) && (solution.m_coords.m_low_color == solution.m_coords.m_high_color))
{
uint s;
if ((solution.m_coords.m_low_color & 31) != 31)
{
solution.m_coords.m_low_color++;
s = 1;
}
else
{
solution.m_coords.m_high_color--;
s = 0;
}
for (uint i = 0; i < m_unique_colors.size(); i++)
solution.m_selectors[i] = static_cast<uint8>(s);
}
if ((pBest_solution) && (solution.m_error < pBest_solution->m_error))
{
*pBest_solution = solution;
return true;
}
return false;
}
bool dxt1_endpoint_optimizer::evaluate_solution_fast(
potential_solution& solution,
const dxt1_solution_coordinates& coords,
bool early_out,
potential_solution* pBest_solution,
bool alternate_rounding)
{
solution.m_coords = coords;
solution.m_selectors.resize(m_unique_colors.size());
if ((pBest_solution) && (early_out))
solution.m_error = pBest_solution->m_error;
else
solution.m_error = cUINT64_MAX;
solution.m_alpha_block = false;
solution.m_valid = false;
uint first_block_type = 0;
uint last_block_type = 1;
if ((m_pParams->m_pixels_have_alpha) || (m_pParams->m_force_alpha_blocks))
first_block_type = 1;
else if (!m_pParams->m_use_alpha_blocks)
last_block_type = 0;
m_trial_selectors.resize(m_unique_colors.size());
color_quad_u8 colors[cDXT1SelectorValues];
colors[0] = dxt1_block::unpack_color(coords.m_low_color, true);
colors[1] = dxt1_block::unpack_color(coords.m_high_color, true);
int vr = colors[1].r - colors[0].r;
int vg = colors[1].g - colors[0].g;
int vb = colors[1].b - colors[0].b;
if (m_perceptual)
{
vr *= 8;
vg *= 24;
}
int stops[4];
stops[0] = colors[0].r*vr + colors[0].g*vg + colors[0].b*vb;
stops[1] = colors[1].r*vr + colors[1].g*vg + colors[1].b*vb;
int dirr = vr * 2;
int dirg = vg * 2;
int dirb = vb * 2;
for (uint block_type = first_block_type; block_type <= last_block_type; block_type++)
{
uint64 trial_error = 0;
if (!block_type)
{
colors[2].set_noclamp_rgba( (colors[0].r * 2 + colors[1].r + alternate_rounding) / 3, (colors[0].g * 2 + colors[1].g + alternate_rounding) / 3, (colors[0].b * 2 + colors[1].b + alternate_rounding) / 3, 255U);
colors[3].set_noclamp_rgba( (colors[1].r * 2 + colors[0].r + alternate_rounding) / 3, (colors[1].g * 2 + colors[0].g + alternate_rounding) / 3, (colors[1].b * 2 + colors[0].b + alternate_rounding) / 3, 255U);
stops[2] = colors[2].r*vr + colors[2].g*vg + colors[2].b*vb;
stops[3] = colors[3].r*vr + colors[3].g*vg + colors[3].b*vb;
// 0 2 3 1
int c0Point = stops[1] + stops[3];
int halfPoint = stops[3] + stops[2];
int c3Point = stops[2] + stops[0];
for (int unique_color_index = (int)m_unique_colors.size() - 1; unique_color_index >= 0; unique_color_index--)
{
const color_quad_u8& c = m_unique_colors[unique_color_index].m_color;
int dot = c.r*dirr + c.g*dirg + c.b*dirb;
uint8 best_color_index;
if (dot < halfPoint)
best_color_index = (dot < c3Point) ? 0 : 2;
else
best_color_index = (dot < c0Point) ? 3 : 1;
uint best_error = color_distance(m_perceptual, c, colors[best_color_index], false);
trial_error += best_error * m_unique_colors[unique_color_index].m_weight;
if (trial_error >= solution.m_error)
break;
m_trial_selectors[unique_color_index] = static_cast<uint8>(best_color_index);
}
}
else
{
colors[2].set_noclamp_rgba( (colors[0].r + colors[1].r + alternate_rounding) >> 1, (colors[0].g + colors[1].g + alternate_rounding) >> 1, (colors[0].b + colors[1].b + alternate_rounding) >> 1, 255U);
stops[2] = colors[2].r*vr + colors[2].g*vg + colors[2].b*vb;
// 0 2 1
int c02Point = stops[0] + stops[2];
int c21Point = stops[2] + stops[1];
for (int unique_color_index = (int)m_unique_colors.size() - 1; unique_color_index >= 0; unique_color_index--)
{
const color_quad_u8& c = m_unique_colors[unique_color_index].m_color;
int dot = c.r*dirr + c.g*dirg + c.b*dirb;
uint8 best_color_index;
if (dot < c02Point)
best_color_index = 0;
else if (dot < c21Point)
best_color_index = 2;
else
best_color_index = 1;
uint best_error = color_distance(m_perceptual, c, colors[best_color_index], false);
trial_error += best_error * m_unique_colors[unique_color_index].m_weight;
if (trial_error >= solution.m_error)
break;
m_trial_selectors[unique_color_index] = static_cast<uint8>(best_color_index);
}
}
if (trial_error < solution.m_error)
{
solution.m_error = trial_error;
solution.m_alpha_block = (block_type != 0);
solution.m_selectors = m_trial_selectors;
solution.m_valid = true;
}
}
if ((!solution.m_alpha_block) && (solution.m_coords.m_low_color == solution.m_coords.m_high_color))
{
uint s;
if ((solution.m_coords.m_low_color & 31) != 31)
{
solution.m_coords.m_low_color++;
s = 1;
}
else
{
solution.m_coords.m_high_color--;
s = 0;
}
for (uint i = 0; i < m_unique_colors.size(); i++)
solution.m_selectors[i] = static_cast<uint8>(s);
}
if ((pBest_solution) && (solution.m_error < pBest_solution->m_error))
{
*pBest_solution = solution;
return true;
}
return false;
}
unique_color dxt1_endpoint_optimizer::lerp_color(const color_quad_u8& a, const color_quad_u8& b, float f, int rounding)
{
color_quad_u8 res;
float r = rounding ? 1.0f : 0.0f;
res[0] = static_cast<uint8>(math::clamp(math::float_to_int(r + math::lerp<float>(a[0], b[0], f)), 0, 255));
res[1] = static_cast<uint8>(math::clamp(math::float_to_int(r + math::lerp<float>(a[1], b[1], f)), 0, 255));
res[2] = static_cast<uint8>(math::clamp(math::float_to_int(r + math::lerp<float>(a[2], b[2], f)), 0, 255));
res[3] = 255;
return unique_color(res, 1);
}
// The block may have been already compressed using another DXTc compressor, such as squish, ATI_Compress, ryg_dxt, etc.
// Attempt to recover the endpoints used by that block compressor.
void dxt1_endpoint_optimizer::try_combinatorial_encoding()
{
if ((m_unique_colors.size() < 2) || (m_unique_colors.size() > 4))
return;
m_temp_unique_colors = m_unique_colors;
if (m_temp_unique_colors.size() == 2)
{
// a b c d
// 0.0 1/3 2/3 1.0
for (uint k = 0; k < 2; k++)
{
for (uint q = 0; q < 2; q++)
{
const uint r = q ^ 1;
// a b
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, 2.0f, k));
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, 3.0f, k));
// a c
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, .5f, k));
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, 1.5f, k));
// a d
// b c
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, -1.0f, k));
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, 2.0f, k));
// b d
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, -.5f, k));
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, .5f, k));
// c d
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, -2.0f, k));
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[q].m_color, m_temp_unique_colors[r].m_color, -1.0f, k));
}
}
}
else if (m_temp_unique_colors.size() == 3)
{
// a b c d
// 0.0 1/3 2/3 1.0
for (uint i = 0; i <= 2; i++)
{
for (uint j = 0; j <= 2; j++)
{
if (i == j)
continue;
// a b c
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[i].m_color, m_temp_unique_colors[j].m_color, 1.5f));
// a b d
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[i].m_color, m_temp_unique_colors[j].m_color, 2.0f/3.0f));
// a c d
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[i].m_color, m_temp_unique_colors[j].m_color, 1.0f/3.0f));
// b c d
m_temp_unique_colors.push_back(lerp_color(m_temp_unique_colors[i].m_color, m_temp_unique_colors[j].m_color, -.5f));
}
}
}
m_unique_packed_colors.resize(0);
for (uint i = 0; i < m_temp_unique_colors.size(); i++)
{
const color_quad_u8& unique_color = m_temp_unique_colors[i].m_color;
const uint16 packed_color = dxt1_block::pack_color(unique_color, true);
if (std::find(m_unique_packed_colors.begin(), m_unique_packed_colors.end(), packed_color) != m_unique_packed_colors.end())
continue;
m_unique_packed_colors.push_back(packed_color);
}
if (m_unique_packed_colors.size() < 2)
return;
for (uint alt_rounding = 0; alt_rounding < 2; alt_rounding++)
{
for (uint i = 0; i < m_unique_packed_colors.size() - 1; i++)
{
for (uint j = i + 1; j < m_unique_packed_colors.size(); j++)
{
evaluate_solution(
dxt1_solution_coordinates(m_unique_packed_colors[i], m_unique_packed_colors[j]),
true,
(alt_rounding == 0) ? &m_best_solution : NULL,
(alt_rounding != 0));
if (m_trial_solution.m_error == 0)
{
if (alt_rounding)
m_best_solution = m_trial_solution;
return;
}
}
}
}
return;
}
// The fourth (transparent) color in 3 color "transparent" blocks is black, which can be optionally exploited for small gains in DXT1 mode if the caller
// doesn't actually use alpha. (But not in DXT5 mode, because 3-color blocks aren't permitted by GPU's for DXT5.)
bool dxt1_endpoint_optimizer::try_alpha_as_black_optimization()
{
const params* pOrig_params = m_pParams;
pOrig_params;
results* pOrig_results = m_pResults;
uint num_dark_colors = 0;
for (uint i = 0; i < m_unique_colors.size(); i++)
if ( (m_unique_colors[i].m_color[0] <= 4) && (m_unique_colors[i].m_color[1] <= 4) && (m_unique_colors[i].m_color[2] <= 4) )
num_dark_colors++;
if ( (!num_dark_colors) || (num_dark_colors == m_unique_colors.size()) )
return true;
params trial_params(*m_pParams);
crnlib::vector<color_quad_u8> trial_colors;
trial_colors.insert(0, m_pParams->m_pPixels, m_pParams->m_num_pixels);
trial_params.m_pPixels = trial_colors.get_ptr();
trial_params.m_pixels_have_alpha = true;
for (uint i = 0; i < trial_colors.size(); i++)
if ( (trial_colors[i][0] <= 4) && (trial_colors[i][1] <= 4) && (trial_colors[i][2] <= 4) )
trial_colors[i][3] = 0;
results trial_results;
crnlib::vector<uint8> trial_selectors(m_pParams->m_num_pixels);
trial_results.m_pSelectors = trial_selectors.get_ptr();
if (!compute_internal(trial_params, trial_results, NULL))
return false;
CRNLIB_ASSERT(trial_results.m_alpha_block);
color_quad_u8 c[4];
dxt1_block::get_block_colors3(c, trial_results.m_low_color, trial_results.m_high_color);
uint64 trial_error = 0;
for (uint i = 0; i < trial_colors.size(); i++)
{
if (trial_colors[i][3] == 0)
{
CRNLIB_ASSERT(trial_selectors[i] == 3);
}
else
{
CRNLIB_ASSERT(trial_selectors[i] != 3);
}
trial_error += color_distance(m_perceptual, trial_colors[i], c[trial_selectors[i]], false);
}
if (trial_error < pOrig_results->m_error)
{
pOrig_results->m_error = trial_error;
pOrig_results->m_low_color = trial_results.m_low_color;
pOrig_results->m_high_color = trial_results.m_high_color;
if (pOrig_results->m_pSelectors)
memcpy(pOrig_results->m_pSelectors, trial_results.m_pSelectors, m_pParams->m_num_pixels);
pOrig_results->m_alpha_block = true;
}
return true;
}
bool dxt1_endpoint_optimizer::compute_internal(const params& p, results& r, solution_vec* pSolutions)
{
clear();
m_pParams = &p;
m_pResults = &r;
m_pSolutions = pSolutions;
m_has_color_weighting = (m_pParams->m_color_weights[0] != 1) || (m_pParams->m_color_weights[1] != 1) || (m_pParams->m_color_weights[2] != 1);
m_perceptual = m_pParams->m_perceptual && !m_has_color_weighting && !m_pParams->m_grayscale_sampling;
find_unique_colors();
m_best_solution.clear();
if (m_unique_colors.empty())
return handle_all_transparent_block();
else if ((m_unique_colors.size() == 1) && (!m_has_transparent_pixels))
return handle_solid_block();
else
{
if (!handle_multicolor_block())
return false;
if ((m_all_pixels_grayscale) && (m_best_solution.m_error))
{
if (!handle_grayscale_block())
return false;
}
}
return true;
}
bool dxt1_endpoint_optimizer::compute(const params& p, results& r, solution_vec* pSolutions)
{
if (!p.m_pPixels)
return false;
bool status = compute_internal(p, r, pSolutions);
if (!status)
return false;
if ( (m_pParams->m_use_alpha_blocks) && (m_pParams->m_use_transparent_indices_for_black) && (!m_pParams->m_pixels_have_alpha) && (!pSolutions) )
{
if (!try_alpha_as_black_optimization())
return false;
}
return true;
}
// Build array of unique colors and their weights.
void dxt1_endpoint_optimizer::find_unique_colors()
{
m_has_transparent_pixels = false;
uint num_opaque_pixels = 0;
const uint alpha_thresh = m_pParams->m_pixels_have_alpha ? (m_pParams->m_dxt1a_alpha_threshold << 24U) : 0;
const uint32* pSrc_pixels = reinterpret_cast<const uint32*>(m_pParams->m_pPixels);
const uint32* pSrc_pixels_end = pSrc_pixels + m_pParams->m_num_pixels;
m_unique_colors.resize(m_pParams->m_num_pixels);
uint num_unique_colors = 0;
m_all_pixels_grayscale = true;
do
{
uint32 c = utils::read_le32(pSrc_pixels);
pSrc_pixels++;
if (c < alpha_thresh)
{
m_has_transparent_pixels = true;
continue;
}
if (m_all_pixels_grayscale)
{
uint r = c & 0xFF;
uint g = (c >> 8) & 0xFF;
uint b = (c >> 16) & 0xFF;
if ((r != g) || (r != b))
m_all_pixels_grayscale = false;
}
c |= 0xFF000000U;
unique_color_hash_map::insert_result ins_result(m_unique_color_hash_map.insert(c, num_unique_colors));
if (ins_result.second)
{
utils::write_le32(&m_unique_colors[num_unique_colors].m_color.m_u32, c);
m_unique_colors[num_unique_colors].m_weight = 1;
num_unique_colors++;
}
else
m_unique_colors[ins_result.first->second].m_weight++;
num_opaque_pixels++;
} while (pSrc_pixels != pSrc_pixels_end);
m_unique_colors.resize(num_unique_colors);
m_total_unique_color_weight = num_opaque_pixels;
}
} // namespace crnlib