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playfield1: alternatively using interleaved organization

This commit is contained in:
Wei-ju Wu 2016-10-10 12:20:08 -07:00
parent 9903393b5c
commit 57f3a4f22d
1 changed files with 18 additions and 1 deletions
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19
hardware/playfield1.c
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@ -23,8 +23,12 @@
#ifdef INTERLEAVED
#include "kingtut-interleaved.h"
// in interleaved mode, skip the following 4 lines = 4 * (320 / 8) = 160 bytes
// that contain the current line for the next 4 bitplanes
#define BPL_MODULO (4 * 40)
#else
#include "kingtut.h"
#define BPL_MODULO 0
#endif /* INTERLEAVED */
#define NUM_COLORS 32
@ -75,7 +79,8 @@ int main(int argc, char **argv)
custom.bplcon0 = 0x5200; // use bitplane 1-5 = BPU 101, composite color enable
#endif
custom.bplcon1 = 0; // horizontal scroll value = 0 for all playfields
custom.bpl1mod = 0; // modulo = 0 for odd bitplanes
custom.bpl1mod = BPL_MODULO; // modulo = 0 for odd bitplanes
custom.bpl2mod = BPL_MODULO; // modulo = 0 for odd bitplanes
custom.dmacon = 0x20;
custom.ddfstrt = DDFSTRT_VALUE;
custom.ddfstop = DDFSTOP_VALUE;
@ -87,11 +92,23 @@ int main(int argc, char **argv)
}
// Initialize copper list with image data address
#ifdef INTERLEAVED
// in interleaved mode, each plane's *rows* are organized
// consecutively one after another
for (int i = 0; i < NUM_BITPLANES; i++) {
ULONG addr = (ULONG) &(image_data[i * 20]);
coplist[i * 4 + 1] = (addr >> 16) & 0xffff;
coplist[i * 4 + 3] = addr & 0xffff;
}
#else
// in non-interleaved mode, each plane's data is placed
// consecutively one after another
for (int i = 0; i < NUM_BITPLANES; i++) {
ULONG addr = (ULONG) &(image_data[i * 20 * NUM_RASTER_LINES]);
coplist[i * 4 + 1] = (addr >> 16) & 0xffff;
coplist[i * 4 + 3] = addr & 0xffff;
}
#endif
// and point to the copper list
custom.cop1lc = (ULONG) coplist;