static void __guac_common_surface_put()

in src/common/surface.c [981:1063]

• 52 lines of code
• 11 McCabe index (conditional complexity)

static void __guac_common_surface_put(unsigned char* src_buffer, int src_stride,
                                      int* sx, int* sy,
                                      guac_common_surface* dst, guac_common_rect* rect,
                                      int opaque) {

    unsigned char* dst_buffer = dst->buffer;
    int dst_stride = dst->stride;

    int x, y;

    int min_x = rect->width;
    int min_y = rect->height;
    int max_x = 0;
    int max_y = 0;

    int orig_x = rect->x;
    int orig_y = rect->y;

    src_buffer += src_stride * (*sy) + 4 * (*sx);
    dst_buffer += (dst_stride * rect->y) + (4 * rect->x);

    /* For each row */
    for (y=0; y < rect->height; y++) {

        uint32_t* src_current = (uint32_t*) src_buffer;
        uint32_t* dst_current = (uint32_t*) dst_buffer;

        /* Copy row */
        for (x=0; x < rect->width; x++) {

            uint32_t color;

            /* Get source and destination color values */
            uint32_t src_color = *src_current;
            uint32_t dst_color = *dst_current;

            /* Ignore alpha channel if opaque */
            if (opaque)
                color = src_color | 0xFF000000;

            /* Otherwise, perform alpha blending operation */
            else
                color = guac_common_surface_argb_blend(dst_color, src_color);

            /* If the destination color is changing, update rectangle bounds
             * and store the new color */
            if (dst_color != color) {
                if (x < min_x) min_x = x;
                if (y < min_y) min_y = y;
                if (x > max_x) max_x = x;
                if (y > max_y) max_y = y;
                *dst_current = color;
            }

            /* Advance to next pixel */
            src_current++;
            dst_current++;

        }

        /* Next row */
        src_buffer += src_stride;
        dst_buffer += dst_stride;

    }

    /* Restrict destination rect to only updated pixels */
    if (max_x >= min_x && max_y >= min_y) {
        rect->x += min_x;
        rect->y += min_y;
        rect->width = max_x - min_x + 1;
        rect->height = max_y - min_y + 1;
    }
    else {
        rect->width = 0;
        rect->height = 0;
    }

    /* Update source X/Y */
    *sx += rect->x - orig_x;
    *sy += rect->y - orig_y;

}