dolphin/Source/Core/VideoCommon/IndexGenerator.cpp

248 lines
5.5 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#include <cstddef>
#include "Common/Common.h"
#include "Common/CommonTypes.h"
#include "VideoCommon/IndexGenerator.h"
#include "VideoCommon/OpcodeDecoding.h"
#include "VideoCommon/VideoConfig.h"
//Init
u16 *IndexGenerator::index_buffer_current;
u16 *IndexGenerator::BASEIptr;
u32 IndexGenerator::base_index;
static const u16 s_primitive_restart = -1;
static u16* (*primitive_table[8])(u16*, u32, u32);
void IndexGenerator::Init()
{
if (g_Config.backend_info.bSupportsPrimitiveRestart)
{
primitive_table[GX_DRAW_QUADS] = IndexGenerator::AddQuads<true>;
primitive_table[GX_DRAW_QUADS_2] = IndexGenerator::AddQuads_nonstandard<true>;
primitive_table[GX_DRAW_TRIANGLES] = IndexGenerator::AddList<true>;
primitive_table[GX_DRAW_TRIANGLE_STRIP] = IndexGenerator::AddStrip<true>;
primitive_table[GX_DRAW_TRIANGLE_FAN] = IndexGenerator::AddFan<true>;
}
else
{
primitive_table[GX_DRAW_QUADS] = IndexGenerator::AddQuads<false>;
primitive_table[GX_DRAW_QUADS_2] = IndexGenerator::AddQuads_nonstandard<false>;
primitive_table[GX_DRAW_TRIANGLES] = IndexGenerator::AddList<false>;
primitive_table[GX_DRAW_TRIANGLE_STRIP] = IndexGenerator::AddStrip<false>;
primitive_table[GX_DRAW_TRIANGLE_FAN] = IndexGenerator::AddFan<false>;
}
primitive_table[GX_DRAW_LINES] = &IndexGenerator::AddLineList;
primitive_table[GX_DRAW_LINE_STRIP] = &IndexGenerator::AddLineStrip;
primitive_table[GX_DRAW_POINTS] = &IndexGenerator::AddPoints;
}
void IndexGenerator::Start(u16* Indexptr)
{
index_buffer_current = Indexptr;
BASEIptr = Indexptr;
base_index = 0;
}
void IndexGenerator::AddIndices(int primitive, u32 numVerts)
{
index_buffer_current = primitive_table[primitive](index_buffer_current, numVerts, base_index);
base_index += numVerts;
}
// Triangles
template <bool pr> __forceinline u16* IndexGenerator::WriteTriangle(u16 *Iptr, u32 index1, u32 index2, u32 index3)
{
*Iptr++ = index1;
*Iptr++ = index2;
*Iptr++ = index3;
if (pr)
*Iptr++ = s_primitive_restart;
return Iptr;
}
template <bool pr> u16* IndexGenerator::AddList(u16 *Iptr, u32 const numVerts, u32 index)
{
for (u32 i = 2; i < numVerts; i+=3)
{
Iptr = WriteTriangle<pr>(Iptr, index + i - 2, index + i - 1, index + i);
}
return Iptr;
}
template <bool pr> u16* IndexGenerator::AddStrip(u16 *Iptr, u32 const numVerts, u32 index)
{
if (pr)
{
for (u32 i = 0; i < numVerts; ++i)
{
*Iptr++ = index + i;
}
*Iptr++ = s_primitive_restart;
}
else
{
bool wind = false;
for (u32 i = 2; i < numVerts; ++i)
{
Iptr = WriteTriangle<pr>(Iptr,
index + i - 2,
index + i - !wind,
index + i - wind);
wind ^= true;
}
}
return Iptr;
}
/**
* FAN simulator:
*
* 2---3
* / \ / \
* 1---0---4
*
* would generate this triangles:
* 012, 023, 034
*
* rotated (for better striping):
* 120, 302, 034
*
* as odd ones have to winded, following strip is fine:
* 12034
*
* so we use 6 indices for 3 triangles
*/
template <bool pr> u16* IndexGenerator::AddFan(u16 *Iptr, u32 numVerts, u32 index)
{
u32 i = 2;
if (pr)
{
for (; i+3<=numVerts; i+=3)
{
*Iptr++ = index + i - 1;
*Iptr++ = index + i + 0;
*Iptr++ = index;
*Iptr++ = index + i + 1;
*Iptr++ = index + i + 2;
*Iptr++ = s_primitive_restart;
}
for (; i+2<=numVerts; i+=2)
{
*Iptr++ = index + i - 1;
*Iptr++ = index + i + 0;
*Iptr++ = index;
*Iptr++ = index + i + 1;
*Iptr++ = s_primitive_restart;
}
}
for (; i < numVerts; ++i)
{
Iptr = WriteTriangle<pr>(Iptr, index, index + i - 1, index + i);
}
return Iptr;
}
/*
* QUAD simulator
*
* 0---1 4---5
* |\ | |\ |
* | \ | | \ |
* | \| | \|
* 3---2 7---6
*
* 012,023, 456,467 ...
* or 120,302, 564,746
* or as strip: 1203, 5647
*
* Warning:
* A simple triangle has to be rendered for three vertices.
* ZWW do this for sun rays
*/
template <bool pr> u16* IndexGenerator::AddQuads(u16 *Iptr, u32 numVerts, u32 index)
{
u32 i = 3;
for (; i < numVerts; i+=4)
{
if (pr)
{
*Iptr++ = index + i - 2;
*Iptr++ = index + i - 1;
*Iptr++ = index + i - 3;
*Iptr++ = index + i - 0;
*Iptr++ = s_primitive_restart;
}
else
{
Iptr = WriteTriangle<pr>(Iptr, index + i - 3, index + i - 2, index + i - 1);
Iptr = WriteTriangle<pr>(Iptr, index + i - 3, index + i - 1, index + i - 0);
}
}
// three vertices remaining, so render a triangle
if (i == numVerts)
{
Iptr = WriteTriangle<pr>(Iptr, index+numVerts-3, index+numVerts-2, index+numVerts-1);
}
return Iptr;
}
template <bool pr> u16* IndexGenerator::AddQuads_nonstandard(u16 *Iptr, u32 numVerts, u32 index)
{
WARN_LOG(VIDEO, "Non-standard primitive drawing command GL_DRAW_QUADS_2");
return AddQuads<pr>(Iptr, numVerts, index);
}
// Lines
u16* IndexGenerator::AddLineList(u16 *Iptr, u32 numVerts, u32 index)
{
for (u32 i = 1; i < numVerts; i+=2)
{
*Iptr++ = index + i - 1;
*Iptr++ = index + i;
}
return Iptr;
}
// shouldn't be used as strips as LineLists are much more common
// so converting them to lists
u16* IndexGenerator::AddLineStrip(u16 *Iptr, u32 numVerts, u32 index)
{
for (u32 i = 1; i < numVerts; ++i)
{
*Iptr++ = index + i - 1;
*Iptr++ = index + i;
}
return Iptr;
}
// Points
u16* IndexGenerator::AddPoints(u16 *Iptr, u32 numVerts, u32 index)
{
for (u32 i = 0; i != numVerts; ++i)
{
*Iptr++ = index + i;
}
return Iptr;
}
u32 IndexGenerator::GetRemainingIndices()
{
u32 max_index = 65534; // -1 is reserved for primitive restart (ogl + dx11)
return max_index - base_index;
}