void gr_rle_expand_scanline(ubyte *dest, ubyte *src, int x1, int x2) {
int i = 0;
ubyte count;
ubyte color = 0;
if (x2 < x1) return;
count = 0;
while (i < x1) {
color = *src++;
if (color == RLE_CODE) return;
if ((color & RLE_CODE) == RLE_CODE) {
count = color & (~RLE_CODE);
color = *src++;
}
else {
// unique
count = 1;
}
i += count;
}
count = i - x1;
i = x1;
// we know have '*count' pixels of 'color'.
if (x1 + count > x2) {
count = x2 - x1 + 1;
rle_stosb(dest, count, color);
return;
}
rle_stosb(dest, count, color);
dest += count;
i += count;
while (i <= x2) {
color = *src++;
if (color == RLE_CODE) return;
if ((color & RLE_CODE) == RLE_CODE) {
count = color & (~RLE_CODE);
color = *src++;
}
else {
// unique
count = 1;
}
// we know have '*count' pixels of 'color'.
if (i + count <= x2) {
rle_stosb(dest, count, color);
i += count;
dest += count;
}
else {
count = x2 - i + 1;
rle_stosb(dest, count, color);
i += count;
dest += count;
}
}
}
// Given pointer to start of one scanline of rle data, uncompress it to
// dest, from source pixels x1 to x2.
void gr_rle_expand_scanline_masked (ubyte *dest, ubyte *src, int x1, int x2 )
{
int i = 0;
ubyte count;
ubyte color=0;
if (x2 < x1) return;
count = 0;
while (i < x1) {
color = *src++;
if (color == RLE_CODE) return;
if (IS_RLE_CODE (color)) {
count = color & (~RLE_CODE);
color = *src++;
} else {
// unique
count = 1;
}
i += count;
}
count = i - x1;
i = x1;
// we know have '*count' pixels of 'color'.
if (x1+count > x2) {
count = x2-x1+1;
if (color != TRANSPARENCY_COLOR)
rle_stosb ((char* )dest, count, color);
return;
}
if (color != TRANSPARENCY_COLOR)
rle_stosb ((char* )dest, count, color);
dest += count;
i += count;
while (i <= x2) {
color = *src++;
if (color == RLE_CODE) return;
if (IS_RLE_CODE (color)) {
count = color & (~RLE_CODE);
color = *src++;
} else {
// unique
count = 1;
}
// we know have '*count' pixels of 'color'.
if (i+count <= x2) {
if (color != TRANSPARENCY_COLOR)
rle_stosb ((char* )dest, count, color);
i += count;
dest += count;
} else {
count = x2-i+1;
if (color != TRANSPARENCY_COLOR)
rle_stosb ((char* )dest, count, color);
i += count;
dest += count;
}
}
}
