mirror of
https://github.com/RaySollium99/picodrive.git
synced 2025-09-05 15:27:46 -04:00
cd: pull in Genesis-Plus-GX CD gfx code
license is the same, code quality is much better, so why not? Many thanks to Eke for writing it.
This commit is contained in:
parent
8e4e84c215
commit
e53f0499fe
2 changed files with 434 additions and 0 deletions
13
pico/cd/genplus_types.h
Normal file
13
pico/cd/genplus_types.h
Normal file
|
@ -0,0 +1,13 @@
|
|||
#undef uint8
|
||||
#undef uint16
|
||||
#undef uint32
|
||||
#undef int8
|
||||
#undef int16
|
||||
#undef int32
|
||||
|
||||
#define uint8 unsigned char
|
||||
#define uint16 unsigned short
|
||||
#define uint32 unsigned int
|
||||
#define int8 signed char
|
||||
#define int16 signed short
|
||||
#define int32 signed int
|
421
pico/cd/gfx.c
Normal file
421
pico/cd/gfx.c
Normal file
|
@ -0,0 +1,421 @@
|
|||
/***************************************************************************************
|
||||
* 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 "genplus_types.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 */
|
||||
uint8 lut_prio[4][0x100][0x100]; /* 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;
|
||||
|
||||
/***************************************************************/
|
||||
/* Rotation / Scaling operation (2M Mode) */
|
||||
/***************************************************************/
|
||||
|
||||
void gfx_init(void)
|
||||
{
|
||||
int i, j;
|
||||
uint16 offset;
|
||||
uint8 mask, row, col, temp;
|
||||
|
||||
memset(&gfx, 0, sizeof(gfx));
|
||||
|
||||
/* Initialize priority modes lookup table */
|
||||
for (i=0; i<0x100; i++)
|
||||
{
|
||||
for (j=0; j<0x100; j++)
|
||||
{
|
||||
/* normal */
|
||||
gfx.lut_prio[0][i][j] = j;
|
||||
/* underwrite */
|
||||
gfx.lut_prio[1][i][j] = ((i & 0x0f) ? (i & 0x0f) : (j & 0x0f)) | ((i & 0xf0) ? (i & 0xf0) : (j & 0xf0));
|
||||
/* overwrite */
|
||||
gfx.lut_prio[2][i][j] = ((j & 0x0f) ? (j & 0x0f) : (i & 0x0f)) | ((j & 0xf0) ? (j & 0xf0) : (i & 0xf0));
|
||||
/* 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;
|
||||
}
|
||||
}
|
||||
|
||||
void gfx_reset(void)
|
||||
{
|
||||
/* Reset cycle counter */
|
||||
gfx.cycles = 0;
|
||||
}
|
||||
|
||||
int gfx_context_save(uint8 *state)
|
||||
{
|
||||
uint32 tmp32;
|
||||
int bufferptr = 0;
|
||||
|
||||
save_param(&gfx.cycles, sizeof(gfx.cycles));
|
||||
save_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine));
|
||||
save_param(&gfx.dotMask, sizeof(gfx.dotMask));
|
||||
save_param(&gfx.stampShift, sizeof(gfx.stampShift));
|
||||
save_param(&gfx.mapShift, sizeof(gfx.mapShift));
|
||||
save_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset));
|
||||
save_param(&gfx.bufferStart, sizeof(gfx.bufferStart));
|
||||
|
||||
tmp32 = (uint8 *)(gfx.tracePtr) - scd.word_ram_2M;
|
||||
save_param(&tmp32, 4);
|
||||
|
||||
tmp32 = (uint8 *)(gfx.mapPtr) - scd.word_ram_2M;
|
||||
save_param(&tmp32, 4);
|
||||
|
||||
return bufferptr;
|
||||
}
|
||||
|
||||
int gfx_context_load(uint8 *state)
|
||||
{
|
||||
uint32 tmp32;
|
||||
int bufferptr = 0;
|
||||
|
||||
load_param(&gfx.cycles, sizeof(gfx.cycles));
|
||||
load_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine));
|
||||
load_param(&gfx.dotMask, sizeof(gfx.dotMask));
|
||||
load_param(&gfx.stampShift, sizeof(gfx.stampShift));
|
||||
load_param(&gfx.mapShift, sizeof(gfx.mapShift));
|
||||
load_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset));
|
||||
load_param(&gfx.bufferStart, sizeof(gfx.bufferStart));
|
||||
|
||||
load_param(&tmp32, 4);
|
||||
gfx.tracePtr = (uint16 *)(scd.word_ram_2M + tmp32);
|
||||
|
||||
load_param(&tmp32, 4);
|
||||
gfx.mapPtr = (uint16 *)(scd.word_ram_2M + tmp32);
|
||||
|
||||
return bufferptr;
|
||||
}
|
||||
|
||||
INLINE void gfx_render(uint32 bufferIndex, uint32 width)
|
||||
{
|
||||
uint8 pixel_in, pixel_out;
|
||||
uint16 stamp_data;
|
||||
uint32 stamp_index;
|
||||
|
||||
/* 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++;
|
||||
|
||||
/* process all dots */
|
||||
while (width--)
|
||||
{
|
||||
/* check if stamp map is repeated */
|
||||
if (scd.regs[0x58>>1].byte.l & 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 | ((scd.regs[0x58>>1].byte.l & 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(scd.word_ram_2M, 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(scd.word_ram_2M, bufferIndex >> 1);
|
||||
|
||||
/* update left or rigth pixel */
|
||||
if (bufferIndex & 1)
|
||||
{
|
||||
pixel_out |= (pixel_in & 0xf0);
|
||||
}
|
||||
else
|
||||
{
|
||||
pixel_out = (pixel_out << 4) | (pixel_in & 0x0f);
|
||||
}
|
||||
|
||||
/* priority mode write */
|
||||
pixel_out = gfx.lut_prio[(scd.regs[0x02>>1].w >> 3) & 0x03][pixel_in][pixel_out];
|
||||
|
||||
/* write data to image buffer */
|
||||
WRITE_BYTE(scd.word_ram_2M, 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, int cycles)
|
||||
{
|
||||
/* make sure 2M mode is enabled */
|
||||
if (!(scd.regs[0x02>>1].byte.l & 0x04))
|
||||
{
|
||||
uint32 mask;
|
||||
|
||||
/* trace vector pointer */
|
||||
gfx.tracePtr = (uint16 *)(scd.word_ram_2M + ((base << 2) & 0x3fff8));
|
||||
|
||||
/* stamps & stamp map size */
|
||||
switch ((scd.regs[0x58>>1].byte.l >> 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 */
|
||||
gfx.mapPtr = (uint16 *)(scd.word_ram_2M + ((scd.regs[0x5a>>1].w << 2) & mask));
|
||||
|
||||
/* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */
|
||||
gfx.bufferOffset = (((scd.regs[0x5c>>1].byte.l & 0x1f) + 1) << 6) - 7;
|
||||
|
||||
/* image buffer start index in dot units (2 pixels/byte) */
|
||||
gfx.bufferStart = (scd.regs[0x5e>>1].w << 3) & 0x7ffc0;
|
||||
|
||||
/* add image buffer horizontal dot offset */
|
||||
gfx.bufferStart += (scd.regs[0x60>>1].byte.l & 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 */
|
||||
scd.regs[0x58>>1].byte.h = 0x80;
|
||||
}
|
||||
}
|
||||
|
||||
void gfx_update(int cycles)
|
||||
{
|
||||
/* synchronize GFX chip with SUB-CPU */
|
||||
cycles -= gfx.cycles;
|
||||
|
||||
/* make sure SUB-CPU is ahead */
|
||||
if (cycles > 0)
|
||||
{
|
||||
/* number of lines to process */
|
||||
unsigned int lines = (cycles + gfx.cyclesPerLine - 1) / gfx.cyclesPerLine;
|
||||
|
||||
/* check against remaining lines */
|
||||
if (lines < scd.regs[0x64>>1].byte.l)
|
||||
{
|
||||
/* update Vdot remaining size */
|
||||
scd.regs[0x64>>1].byte.l -= lines;
|
||||
|
||||
/* increment cycle counter */
|
||||
gfx.cycles += lines * gfx.cyclesPerLine;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* process remaining lines */
|
||||
lines = scd.regs[0x64>>1].byte.l;
|
||||
|
||||
/* clear Vdot remaining size */
|
||||
scd.regs[0x64>>1].byte.l = 0;
|
||||
|
||||
/* end of graphics operation */
|
||||
scd.regs[0x58>>1].byte.h = 0;
|
||||
|
||||
/* level 1 interrupt enabled ? */
|
||||
if (scd.regs[0x32>>1].byte.l & 0x02)
|
||||
{
|
||||
/* trigger level 1 interrupt */
|
||||
scd.pending |= (1 << 1);
|
||||
|
||||
/* update IRQ level */
|
||||
s68k_update_irq((scd.pending & scd.regs[0x32>>1].byte.l) >> 1);
|
||||
}
|
||||
}
|
||||
|
||||
/* render lines */
|
||||
while (lines--)
|
||||
{
|
||||
/* process dots to image buffer */
|
||||
gfx_render(gfx.bufferStart, scd.regs[0x62>>1].w);
|
||||
|
||||
/* increment image buffer start index for next line (8 pixels/line) */
|
||||
gfx.bufferStart += 8;
|
||||
}
|
||||
}
|
||||
}
|
Loading…
Add table
Add a link
Reference in a new issue