in cores/gba/src/gb/renderers/software.c [703:843]
static void GBVideoSoftwareRendererDrawObj(struct GBVideoSoftwareRenderer* renderer, struct GBObj* obj, int startX, int endX, int y) {
int ix = obj->x - 8;
if (endX < ix || startX >= ix + 8) {
return;
}
if (obj->x < endX) {
endX = obj->x;
}
if (obj->x - 8 > startX) {
startX = obj->x - 8;
}
if (startX < 0) {
startX = 0;
}
uint8_t* data = renderer->d.vram;
int tileOffset = 0;
int bottomY;
if (GBObjAttributesIsYFlip(obj->attr)) {
bottomY = 7 - ((y - obj->y - 16) & 7);
if (GBRegisterLCDCIsObjSize(renderer->lcdc) && y - obj->y < -8) {
++tileOffset;
}
} else {
bottomY = (y - obj->y - 16) & 7;
if (GBRegisterLCDCIsObjSize(renderer->lcdc) && y - obj->y >= -8) {
++tileOffset;
}
}
if (GBRegisterLCDCIsObjSize(renderer->lcdc) && obj->tile & 1) {
--tileOffset;
}
uint8_t mask = GBObjAttributesIsPriority(obj->attr) ? 0x63 : 0x60;
uint8_t mask2 = GBObjAttributesIsPriority(obj->attr) ? 0 : 0x83;
int p;
if (renderer->model >= GB_MODEL_CGB) {
p = (GBObjAttributesGetCGBPalette(obj->attr) + 8) * 4;
if (GBObjAttributesIsBank(obj->attr)) {
data += GB_SIZE_VRAM_BANK0;
}
if (!GBRegisterLCDCIsBgEnable(renderer->lcdc)) {
mask = 0x60;
mask2 = 0x83;
}
} else {
p = (GBObjAttributesGetPalette(obj->attr) + 8) * 4;
}
int bottomX;
int x = startX;
if ((x - obj->x) & 7) {
for (; x < endX; ++x) {
if (GBObjAttributesIsXFlip(obj->attr)) {
bottomX = (x - obj->x) & 7;
} else {
bottomX = 7 - ((x - obj->x) & 7);
}
int objTile = obj->tile + tileOffset;
uint8_t tileDataLower = data[(objTile * 8 + bottomY) * 2];
uint8_t tileDataUpper = data[(objTile * 8 + bottomY) * 2 + 1];
tileDataUpper >>= bottomX;
tileDataLower >>= bottomX;
color_t current = renderer->row[x];
if (((tileDataUpper | tileDataLower) & 1) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
}
}
} else if (GBObjAttributesIsXFlip(obj->attr)) {
int objTile = obj->tile + tileOffset;
uint8_t tileDataLower = data[(objTile * 8 + bottomY) * 2];
uint8_t tileDataUpper = data[(objTile * 8 + bottomY) * 2 + 1];
color_t current;
current = renderer->row[x];
if (((tileDataUpper | tileDataLower) & 1) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
}
current = renderer->row[x + 1];
if (((tileDataUpper | tileDataLower) & 2) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 1] = p | (tileDataUpper & 2) | ((tileDataLower & 2) >> 1);
}
current = renderer->row[x + 2];
if (((tileDataUpper | tileDataLower) & 4) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 2] = p | ((tileDataUpper & 4) >> 1) | ((tileDataLower & 4) >> 2);
}
current = renderer->row[x + 3];
if (((tileDataUpper | tileDataLower) & 8) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 3] = p | ((tileDataUpper & 8) >> 2) | ((tileDataLower & 8) >> 3);
}
current = renderer->row[x + 4];
if (((tileDataUpper | tileDataLower) & 16) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 4] = p | ((tileDataUpper & 16) >> 3) | ((tileDataLower & 16) >> 4);
}
current = renderer->row[x + 5];
if (((tileDataUpper | tileDataLower) & 32) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 5] = p | ((tileDataUpper & 32) >> 4) | ((tileDataLower & 32) >> 5);
}
current = renderer->row[x + 6];
if (((tileDataUpper | tileDataLower) & 64) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 6] = p | ((tileDataUpper & 64) >> 5) | ((tileDataLower & 64) >> 6);
}
current = renderer->row[x + 7];
if (((tileDataUpper | tileDataLower) & 128) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 7] = p | ((tileDataUpper & 128) >> 6) | ((tileDataLower & 128) >> 7);
}
} else {
int objTile = obj->tile + tileOffset;
uint8_t tileDataLower = data[(objTile * 8 + bottomY) * 2];
uint8_t tileDataUpper = data[(objTile * 8 + bottomY) * 2 + 1];
color_t current;
current = renderer->row[x + 7];
if (((tileDataUpper | tileDataLower) & 1) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 7] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
}
current = renderer->row[x + 6];
if (((tileDataUpper | tileDataLower) & 2) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 6] = p | (tileDataUpper & 2) | ((tileDataLower & 2) >> 1);
}
current = renderer->row[x + 5];
if (((tileDataUpper | tileDataLower) & 4) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 5] = p | ((tileDataUpper & 4) >> 1) | ((tileDataLower & 4) >> 2);
}
current = renderer->row[x + 4];
if (((tileDataUpper | tileDataLower) & 8) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 4] = p | ((tileDataUpper & 8) >> 2) | ((tileDataLower & 8) >> 3);
}
current = renderer->row[x + 3];
if (((tileDataUpper | tileDataLower) & 16) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 3] = p | ((tileDataUpper & 16) >> 3) | ((tileDataLower & 16) >> 4);
}
current = renderer->row[x + 2];
if (((tileDataUpper | tileDataLower) & 32) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 2] = p | ((tileDataUpper & 32) >> 4) | ((tileDataLower & 32) >> 5);
}
current = renderer->row[x + 1];
if (((tileDataUpper | tileDataLower) & 64) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x + 1] = p | ((tileDataUpper & 64) >> 5) | ((tileDataLower & 64) >> 6);
}
current = renderer->row[x];
if (((tileDataUpper | tileDataLower) & 128) && !(current & mask) && (current & mask2) <= 0x80) {
renderer->row[x] = p | ((tileDataUpper & 128) >> 6) | ((tileDataLower & 128) >> 7);
}
}
}