warp.cl

__kernel void teste2(__global __read_only uchar * srcptr, int src_step, int src_offset,
                     __global uchar * dstptr, int dst_step, int dst_offset, int rows, int cols,
                    float focal)
{
    int du = get_global_id(0);
    int dv = get_global_id(1);

    if (du < cols && dv < rows) {
        du = du - (0.5 * cols) + 1;
        dv = dv - (0.5 * rows) + 1;

        const float f = du / focal;
        float x = focal * tan(f);
        float y = dv * sqrt(1 + pow(tan(f), 2));

        x = x + (0.5 * cols) - 1;
        y = y + (0.5 * rows) - 1;

        if (x >= 0 && x < cols && y >= 0 && y < rows) {
            int i = get_global_id(0);
            int j = get_global_id(1);

#if 0
            int dst_index = mad24(j, dst_step, mad24(i, sizeof(uchar)*3, dst_offset));
            int src_index = mad24(y, src_step, mad24(x, sizeof(uchar)*3, src_offset));

            __global uchar *dst = (__global uchar *)(dstptr + dst_index);
            __global __read_only uchar *src = (__global __read_only uchar *)(srcptr + src_index);

            dst[0] = src[0];
            dst[1] = src[1];
            dst[2] = src[2];
#else
            int dst_index = mad24(j, dst_step, mad24(i, sizeof(uchar3), dst_offset));
            int src_index = mad24(y, src_step, mad24(x, sizeof(uchar3), src_offset));

            __global uchar3 *dst = (__global uchar3 *)(dstptr + dst_index);
            __global __read_only uchar3 *src = (__global __read_only uchar3 *)(srcptr + src_index);

            dst[0] = src[0];
#endif
        }
    }
}