    var filters = [gl.LINEAR, gl.NEAREST];
    var drawbuffersFormats = [linearMask, srgbMask, linearMask | srgbMask];
    for (var ii = 0; ii < filters.length; ++ii) {
        for (var jj = 0; jj < drawbuffersFormats.length; ++jj) {
            blitframebuffer_srgb_and_linear_drawbuffers(gl.SRGB8_ALPHA8, drawbuffersFormats[jj], filters[ii]);
            blitframebuffer_srgb_and_linear_drawbuffers(gl.RGBA8, drawbuffersFormats[jj], filters[ii]);
        }
    }
}

function blitframebuffer_srgb_and_linear_dra