server/utils.c


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#include <glib.h>
#include "utils.h"

int rgb32_data_has_alpha(int width, int height, size_t stride,
                         uint8_t *data, int *all_set_out)
{
    uint32_t *line, *end, alpha;
    int has_alpha;

    has_alpha = FALSE;
    while (height-- > 0) {
        line = (uint32_t *)data;
        end = line + width;
        data += stride;
        while (line != end) {
            alpha = *line & 0xff000000U;
            if (alpha != 0) {
                has_alpha = TRUE;
                if (alpha != 0xff000000U) {
                    *all_set_out = FALSE;
                    return TRUE;
                }
            }
            line++;
        }
    }

    *all_set_out = has_alpha;
    return has_alpha;
}