- int width = src_rect.width;
- int height = src_rect.height;
-
- int xoffs = dest_x - dest_rect.x;
- if(xoffs < 0) {
- dest_x = dest_rect.x;
- width += xoffs;
- }
-
- int yoffs = dest_y - dest_rect.y;
- if(yoffs < 0) {
- dest_y = dest_rect.y;
- height += yoffs;
- }
-
- int xend = dest_x + width;
- if(xend >= dest_rect.width) {
- width -= xend - dest_rect.width;
- }
-
- int yend = dest_y + height;
- if(yend >= dest_rect.height) {
- height -= yend - dest_rect.height;
- }
-
- if(width <= 0 || height <= 0) {
- return;
- }
-
- unsigned char *sptr = src_img + (src_rect.y * src_rect.width + src_rect.x) * 4;
- unsigned char *dptr = dest_img + (dest_y * dest_rect.width + dest_x) * 4;
-
- for(int i=0; i<height; i++) {
- memcpy(dptr, sptr, width * 4);
- sptr += src_rect.width * 4;
- dptr += dest_rect.width * 4;
- }