apple1-videocard-lib/lib/sprites.h

51 lines
1.4 KiB
C

#ifndef SPRITES_H
#define SPRITES_H
typedef struct {
signed char y;
byte x;
byte name;
byte color;
} tms_sprite;
#define SIZEOF_SPRITE 4
#define SPRITE_OFF_MARKER 0xD0
#define EARLY_CLOCK 128
void tms_set_total_sprites(byte num) {
// write the value 0xD0 as Y coordinate of the first unused sprite
word addr = TMS_SPRITE_ATTRS + (word) (num * SIZEOF_SPRITE);
tms_set_vram_write_addr(addr);
TMS_WRITE_DATA_PORT(SPRITE_OFF_MARKER); // 0xD0 oi the sprite off indicator
}
void tms_set_sprite(byte sprite_num, tms_sprite *s) {
word addr = TMS_SPRITE_ATTRS + (word) (sprite_num * SIZEOF_SPRITE);
tms_set_vram_write_addr(addr);
// TODO verify NOPs on real machine
// TODO is it better to use tms_copy_to_vram() ?
TMS_WRITE_DATA_PORT(s->y); NOP; // y coordinate
TMS_WRITE_DATA_PORT(s->x); NOP; // x coordinate
TMS_WRITE_DATA_PORT(s->name); NOP; // name
TMS_WRITE_DATA_PORT(s->color); NOP; // color
}
void tms_set_sprite_double_size(byte size) {
byte regval = tms_regs_latch[1] & (REG1_SIZE_MASK ^ 0xFF);
if(size) regval |= REG1_SIZE_MASK;
tms_write_reg(1, regval);
}
void tms_set_sprite_magnification(byte m) {
byte regval = tms_regs_latch[1] & (REG1_MAG_MASK ^ 0xFF);
if(m) regval |= REG1_MAG_MASK;
tms_write_reg(1, regval);
}
// clear the collision flag by reading the status register
inline void tms_clear_collisions() {
asm { lda VDP_REG };
}
#endif