404 lines
13 KiB
C
404 lines
13 KiB
C
/***************************************************************************************
|
|
* Genesis Plus
|
|
* CD graphics processor
|
|
*
|
|
* Copyright (C) 2012 Eke-Eke (Genesis Plus GX)
|
|
*
|
|
* Redistribution and use of this code or any derivative works are permitted
|
|
* provided that the following conditions are met:
|
|
*
|
|
* - Redistributions may not be sold, nor may they be used in a commercial
|
|
* product or activity.
|
|
*
|
|
* - Redistributions that are modified from the original source must include the
|
|
* complete source code, including the source code for all components used by a
|
|
* binary built from the modified sources. However, as a special exception, the
|
|
* source code distributed need not include anything that is normally distributed
|
|
* (in either source or binary form) with the major components (compiler, kernel,
|
|
* and so on) of the operating system on which the executable runs, unless that
|
|
* component itself accompanies the executable.
|
|
*
|
|
* - Redistributions must reproduce the above copyright notice, this list of
|
|
* conditions and the following disclaimer in the documentation and/or other
|
|
* materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************************/
|
|
#include "../pico_int.h"
|
|
#include "genplus_macros.h"
|
|
|
|
typedef struct
|
|
{
|
|
//uint32 cycles; /* current cycles count for graphics operation */
|
|
//uint32 cyclesPerLine; /* current graphics operation timings */
|
|
uint32 dotMask; /* stamp map size mask */
|
|
uint16 *tracePtr; /* trace vector pointer */
|
|
uint16 *mapPtr; /* stamp map table base address */
|
|
uint8 stampShift; /* stamp pixel shift value (related to stamp size) */
|
|
uint8 mapShift; /* stamp map table shift value (related to stamp map size) */
|
|
uint16 bufferOffset; /* image buffer column offset */
|
|
uint32 bufferStart; /* image buffer start index */
|
|
uint32 y_step; /* pico: render line step */
|
|
uint8 lut_prio[4][0x10][0x10]; /* WORD-RAM data writes priority lookup table */
|
|
uint8 lut_pixel[0x200]; /* Graphics operation dot offset lookup table */
|
|
uint8 lut_cell[0x100]; /* Graphics operation stamp offset lookup table */
|
|
} gfx_t;
|
|
|
|
static gfx_t gfx;
|
|
|
|
static void gfx_schedule(void);
|
|
|
|
/***************************************************************/
|
|
/* Rotation / Scaling operation (2M Mode) */
|
|
/***************************************************************/
|
|
|
|
void gfx_init(void)
|
|
{
|
|
int i, j;
|
|
uint8 mask, row, col, temp;
|
|
|
|
memset(&gfx, 0, sizeof(gfx));
|
|
|
|
/* Initialize priority modes lookup table */
|
|
for (i = 0; i < 0x10; i++)
|
|
{
|
|
for (j = 0; j < 0x10; j++)
|
|
{
|
|
/* normal */
|
|
gfx.lut_prio[0][i][j] = j;
|
|
/* underwrite */
|
|
gfx.lut_prio[1][i][j] = i ? i : j;
|
|
/* overwrite */
|
|
gfx.lut_prio[2][i][j] = j ? j : i;
|
|
/* invalid */
|
|
gfx.lut_prio[3][i][j] = i;
|
|
}
|
|
}
|
|
|
|
/* Initialize cell lookup table */
|
|
/* table entry = yyxxshrr (8 bits) */
|
|
/* with: yy = cell row (0-3) */
|
|
/* xx = cell column (0-3) */
|
|
/* s = stamp size (0=16x16, 1=32x32) */
|
|
/* hrr = HFLIP & ROTATION bits */
|
|
for (i=0; i<0x100; i++)
|
|
{
|
|
/* one stamp = 2x2 cells (16x16) or 4x4 cells (32x32) */
|
|
mask = (i & 8) ? 3 : 1;
|
|
row = (i >> 6) & mask;
|
|
col = (i >> 4) & mask;
|
|
|
|
if (i & 4) { col = col ^ mask; } /* HFLIP (always first) */
|
|
if (i & 2) { col = col ^ mask; row = row ^ mask; } /* ROLL1 */
|
|
if (i & 1) { temp = col; col = row ^ mask; row = temp; } /* ROLL0 */
|
|
|
|
/* cell offset (0-3 or 0-15) */
|
|
gfx.lut_cell[i] = row + col * (mask + 1);
|
|
}
|
|
|
|
/* Initialize pixel lookup table */
|
|
/* table entry = yyyxxxhrr (9 bits) */
|
|
/* with: yyy = pixel row (0-7) */
|
|
/* xxx = pixel column (0-7) */
|
|
/* hrr = HFLIP & ROTATION bits */
|
|
for (i=0; i<0x200; i++)
|
|
{
|
|
/* one cell = 8x8 pixels */
|
|
row = (i >> 6) & 7;
|
|
col = (i >> 3) & 7;
|
|
|
|
if (i & 4) { col = col ^ 7; } /* HFLIP (always first) */
|
|
if (i & 2) { col = col ^ 7; row = row ^ 7; } /* ROLL1 */
|
|
if (i & 1) { temp = col; col = row ^ 7; row = temp; } /* ROLL0 */
|
|
|
|
/* pixel offset (0-63) */
|
|
gfx.lut_pixel[i] = col + row * 8;
|
|
}
|
|
}
|
|
|
|
static void gfx_render(uint32 bufferIndex, uint32 width)
|
|
{
|
|
uint8 pixel_in, pixel_out;
|
|
uint16 stamp_data;
|
|
uint32 stamp_index;
|
|
uint32 priority;
|
|
|
|
/* pixel map start position for current line (13.3 format converted to 13.11) */
|
|
uint32 xpos = *gfx.tracePtr++ << 8;
|
|
uint32 ypos = *gfx.tracePtr++ << 8;
|
|
|
|
/* pixel map offset values for current line (5.11 format) */
|
|
uint32 xoffset = (int16) *gfx.tracePtr++;
|
|
uint32 yoffset = (int16) *gfx.tracePtr++;
|
|
|
|
priority = (Pico_mcd->s68k_regs[2] << 8) | Pico_mcd->s68k_regs[3];
|
|
priority = (priority >> 3) & 0x03;
|
|
|
|
/* process all dots */
|
|
while (width--)
|
|
{
|
|
/* check if stamp map is repeated */
|
|
if (Pico_mcd->s68k_regs[0x58+1] & 0x01)
|
|
{
|
|
/* stamp map range */
|
|
xpos &= gfx.dotMask;
|
|
ypos &= gfx.dotMask;
|
|
}
|
|
else
|
|
{
|
|
/* 24-bit range */
|
|
xpos &= 0xffffff;
|
|
ypos &= 0xffffff;
|
|
}
|
|
|
|
/* check if pixel is outside stamp map */
|
|
if ((xpos | ypos) & ~gfx.dotMask)
|
|
{
|
|
/* force pixel output to 0 */
|
|
pixel_out = 0x00;
|
|
}
|
|
else
|
|
{
|
|
/* read stamp map table data */
|
|
stamp_data = gfx.mapPtr[(xpos >> gfx.stampShift) | ((ypos >> gfx.stampShift) << gfx.mapShift)];
|
|
|
|
/* stamp generator base index */
|
|
/* sss ssssssss ccyyyxxx (16x16) or sss sssssscc ccyyyxxx (32x32) */
|
|
/* with: s = stamp number (1 stamp = 16x16 or 32x32 pixels) */
|
|
/* c = cell offset (0-3 for 16x16, 0-15 for 32x32) */
|
|
/* yyy = line offset (0-7) */
|
|
/* xxx = pixel offset (0-7) */
|
|
stamp_index = (stamp_data & 0x7ff) << 8;
|
|
|
|
if (stamp_index)
|
|
{
|
|
/* extract HFLIP & ROTATION bits */
|
|
stamp_data = (stamp_data >> 13) & 7;
|
|
|
|
/* cell offset (0-3 or 0-15) */
|
|
/* table entry = yyxxshrr (8 bits) */
|
|
/* with: yy = cell row (0-3) = (ypos >> (11 + 3)) & 3 */
|
|
/* xx = cell column (0-3) = (xpos >> (11 + 3)) & 3 */
|
|
/* s = stamp size (0=16x16, 1=32x32) */
|
|
/* hrr = HFLIP & ROTATION bits */
|
|
stamp_index |= gfx.lut_cell[
|
|
stamp_data | ((Pico_mcd->s68k_regs[0x58+1] & 0x02) << 2 )
|
|
| ((ypos >> 8) & 0xc0) | ((xpos >> 10) & 0x30)] << 6;
|
|
|
|
/* pixel offset (0-63) */
|
|
/* table entry = yyyxxxhrr (9 bits) */
|
|
/* with: yyy = pixel row (0-7) = (ypos >> 11) & 7 */
|
|
/* xxx = pixel column (0-7) = (xpos >> 11) & 7 */
|
|
/* hrr = HFLIP & ROTATION bits */
|
|
stamp_index |= gfx.lut_pixel[stamp_data | ((xpos >> 8) & 0x38) | ((ypos >> 5) & 0x1c0)];
|
|
|
|
/* read pixel pair (2 pixels/byte) */
|
|
pixel_out = READ_BYTE(Pico_mcd->word_ram2M, stamp_index >> 1);
|
|
|
|
/* extract left or rigth pixel */
|
|
if (stamp_index & 1)
|
|
{
|
|
pixel_out &= 0x0f;
|
|
}
|
|
else
|
|
{
|
|
pixel_out >>= 4;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* stamp 0 is not used: force pixel output to 0 */
|
|
pixel_out = 0x00;
|
|
}
|
|
}
|
|
|
|
/* read out paired pixel data */
|
|
pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1);
|
|
|
|
/* update left or rigth pixel */
|
|
if (bufferIndex & 1)
|
|
{
|
|
/* priority mode write */
|
|
pixel_out = gfx.lut_prio[priority][pixel_in & 0x0f][pixel_out];
|
|
|
|
pixel_out |= (pixel_in & 0xf0);
|
|
}
|
|
else
|
|
{
|
|
/* priority mode write */
|
|
pixel_out = gfx.lut_prio[priority][pixel_in >> 4][pixel_out];
|
|
|
|
pixel_out = (pixel_out << 4) | (pixel_in & 0x0f);
|
|
}
|
|
|
|
/* write data to image buffer */
|
|
WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_out);
|
|
|
|
/* check current pixel position */
|
|
if ((bufferIndex & 7) != 7)
|
|
{
|
|
/* next pixel */
|
|
bufferIndex++;
|
|
}
|
|
else
|
|
{
|
|
/* next cell: increment image buffer offset by one column (minus 7 pixels) */
|
|
bufferIndex += gfx.bufferOffset;
|
|
}
|
|
|
|
/* increment pixel position */
|
|
xpos += xoffset;
|
|
ypos += yoffset;
|
|
}
|
|
}
|
|
|
|
void gfx_start(unsigned int base)
|
|
{
|
|
/* make sure 2M mode is enabled */
|
|
if (!(Pico_mcd->s68k_regs[3] & 0x04))
|
|
{
|
|
uint32 mask = 0;
|
|
uint32 reg;
|
|
|
|
/* trace vector pointer */
|
|
gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + ((base << 2) & 0x3fff8));
|
|
|
|
/* stamps & stamp map size */
|
|
switch ((Pico_mcd->s68k_regs[0x58+1] >> 1) & 0x03)
|
|
{
|
|
case 0:
|
|
gfx.dotMask = 0x07ffff; /* 256x256 dots/map */
|
|
gfx.stampShift = 11 + 4; /* 16x16 dots/stamps */
|
|
gfx.mapShift = 4; /* 16x16 stamps/map */
|
|
mask = 0x3fe00; /* 512 bytes/table */
|
|
break;
|
|
|
|
case 1:
|
|
gfx.dotMask = 0x07ffff; /* 256x256 dots/map */
|
|
gfx.stampShift = 11 + 5; /* 32x32 dots/stamps */
|
|
gfx.mapShift = 3; /* 8x8 stamps/map */
|
|
mask = 0x3ff80; /* 128 bytes/table */
|
|
break;
|
|
|
|
case 2:
|
|
gfx.dotMask = 0x7fffff; /* 4096*4096 dots/map */
|
|
gfx.stampShift = 11 + 4; /* 16x16 dots/stamps */
|
|
gfx.mapShift = 8; /* 256x256 stamps/map */
|
|
mask = 0x20000; /* 131072 bytes/table */
|
|
break;
|
|
|
|
case 3:
|
|
gfx.dotMask = 0x7fffff; /* 4096*4096 dots/map */
|
|
gfx.stampShift = 11 + 5; /* 32x32 dots/stamps */
|
|
gfx.mapShift = 7; /* 128x128 stamps/map */
|
|
mask = 0x38000; /* 32768 bytes/table */
|
|
break;
|
|
}
|
|
|
|
/* stamp map table base address */
|
|
reg = (Pico_mcd->s68k_regs[0x5a] << 8) | Pico_mcd->s68k_regs[0x5b];
|
|
gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + ((reg << 2) & mask));
|
|
|
|
/* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */
|
|
gfx.bufferOffset = (((Pico_mcd->s68k_regs[0x5c+1] & 0x1f) + 1) << 6) - 7;
|
|
|
|
/* image buffer start index in dot units (2 pixels/byte) */
|
|
reg = (Pico_mcd->s68k_regs[0x5e] << 8) | Pico_mcd->s68k_regs[0x5f];
|
|
gfx.bufferStart = (reg << 3) & 0x7ffc0;
|
|
|
|
/* add image buffer horizontal dot offset */
|
|
gfx.bufferStart += (Pico_mcd->s68k_regs[0x60+1] & 0x3f);
|
|
|
|
/* reset GFX chip cycle counter */
|
|
//gfx.cycles = cycles;
|
|
|
|
/* update GFX chip timings (see AC3:Thunderhawk / Thunderstrike) */
|
|
//gfx.cyclesPerLine = 4 * 5 * scd.regs[0x62>>1].w;
|
|
|
|
/* start graphics operation */
|
|
Pico_mcd->s68k_regs[0x58] = 0x80;
|
|
|
|
gfx_schedule();
|
|
}
|
|
}
|
|
|
|
/* PicoDrive specific */
|
|
#define UPDATE_CYCLES 20000
|
|
|
|
static void gfx_schedule(void)
|
|
{
|
|
int w, h, cycles;
|
|
int y_step;
|
|
|
|
w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63];
|
|
h = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65];
|
|
|
|
cycles = 5 * w * h;
|
|
if (cycles > UPDATE_CYCLES)
|
|
y_step = (UPDATE_CYCLES + 5 * w - 1) / (5 * w);
|
|
else
|
|
y_step = h;
|
|
|
|
gfx.y_step = y_step;
|
|
pcd_event_schedule_s68k(PCD_EVENT_GFX, 5 * w * y_step);
|
|
}
|
|
|
|
void gfx_update(unsigned int cycles)
|
|
{
|
|
int lines, lines_reg;
|
|
int w;
|
|
|
|
if (!(Pico_mcd->s68k_regs[0x58] & 0x80))
|
|
return;
|
|
|
|
w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63];
|
|
lines = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65];
|
|
lines_reg = lines - gfx.y_step;
|
|
|
|
if (lines_reg <= 0) {
|
|
Pico_mcd->s68k_regs[0x58] = 0;
|
|
Pico_mcd->s68k_regs[0x64] =
|
|
Pico_mcd->s68k_regs[0x65] = 0;
|
|
|
|
if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN1) {
|
|
elprintf(EL_INTS|EL_CD, "s68k: gfx_cd irq 1");
|
|
SekInterruptS68k(1);
|
|
}
|
|
}
|
|
else {
|
|
Pico_mcd->s68k_regs[0x64] = lines_reg >> 8;
|
|
Pico_mcd->s68k_regs[0x65] = lines_reg;
|
|
|
|
if (lines > gfx.y_step)
|
|
lines = gfx.y_step;
|
|
|
|
pcd_event_schedule(cycles, PCD_EVENT_GFX, 5 * w * lines);
|
|
}
|
|
|
|
if (PicoOpt & POPT_EN_MCD_GFX)
|
|
{
|
|
/* render lines */
|
|
while (lines--)
|
|
{
|
|
/* process dots to image buffer */
|
|
gfx_render(gfx.bufferStart, w);
|
|
|
|
/* increment image buffer start index for next line (8 pixels/line) */
|
|
gfx.bufferStart += 8;
|
|
}
|
|
}
|
|
}
|
|
|
|
// vim:shiftwidth=2:ts=2:expandtab
|