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Kjell Andersson

The speed of glDrawPixels

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on my card its very slow (vanta) i hear its a bit quicker on geforces+

glDrawPixels: LUMINANCE -- UNSIGNED_BYTE rate 0.661 Mpixels/sec
glDrawPixels: LUMINANCE -- UNSIGNED_SHORT rate 0.636 Mpixels/sec
glDrawPixels: LUMINANCE -- UNSIGNED_INT rate 0.641 Mpixels/sec
glDrawPixels: LUMINANCE -- FLOAT rate 0.631 Mpixels/sec
glDrawPixels: ALPHA -- UNSIGNED_BYTE rate 0.667 Mpixels/sec
glDrawPixels: ALPHA -- UNSIGNED_SHORT rate 0.635 Mpixels/sec
glDrawPixels: ALPHA -- UNSIGNED_INT rate 0.636 Mpixels/sec
glDrawPixels: ALPHA -- FLOAT rate 0.629 Mpixels/sec
glDrawPixels: RED -- UNSIGNED_BYTE rate 0.667 Mpixels/sec
glDrawPixels: RED -- UNSIGNED_SHORT rate 0.633 Mpixels/sec
glDrawPixels: RED -- UNSIGNED_INT rate 0.638 Mpixels/sec
glDrawPixels: RED -- FLOAT rate 0.627 Mpixels/sec
glDrawPixels: RGB -- UNSIGNED_BYTE rate 0.676 Mpixels/sec
glDrawPixels: BGR -- UNSIGNED_BYTE rate 0.625 Mpixels/sec
glDrawPixels: RGBA -- UNSIGNED_BYTE rate 0.657 Mpixels/sec
glDrawPixels: BGRA -- UNSIGNED_BYTE rate 0.618 Mpixels/sec
glDrawPixels: RGB -- UNSIGNED_SHORT_5_6_5 rate 0.595 Mpixels/sec
glDrawPixels: BGR -- UNSIGNED_SHORT_5_6_5 rate 313698.039 Mpixels/sec
glDrawPixels: RGB -- UNSIGNED_SHORT_5_6_5_REV rate 0.598 Mpixels/sec
glDrawPixels: BGR -- UNSIGNED_SHORT_5_6_5_REV rate 312805.584 Mpixels/sec
glDrawPixels: RGBA -- UNSIGNED_INT_8_8_8_8 rate 0.572 Mpixels/sec
glDrawPixels: BGRA -- UNSIGNED_INT_8_8_8_8 rate 0.563 Mpixels/sec
glDrawPixels: RGBA -- UNSIGNED_INT_8_8_8_8_REV rate 0.571 Mpixels/sec
glDrawPixels: BGRA -- UNSIGNED_INT_8_8_8_8_REV rate 0.563 Mpixels/sec

ignore the 2 obvious invalid data ones
drawpixels is slow it aint optimized with any method though with a geforce i think a couple of methods are,
readpixels is about 30x quicker than drawpixels
copypixels about 250x quicker than drawpixels

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my own program sorry i dont have a site to upload it at present
heres readpixel performance for a comparrison

glReadPixels: LUMINANCE -- UNSIGNED_BYTE rate 3.708 Mpixels/sec
glReadPixels: LUMINANCE -- UNSIGNED_SHORT rate 3.548 Mpixels/sec
glReadPixels: LUMINANCE -- UNSIGNED_INT rate 2.366 Mpixels/sec
glReadPixels: LUMINANCE -- FLOAT rate 3.738 Mpixels/sec
glReadPixels: ALPHA -- UNSIGNED_BYTE rate 21.468 Mpixels/sec
glReadPixels: ALPHA -- UNSIGNED_SHORT rate 16.836 Mpixels/sec
glReadPixels: ALPHA -- UNSIGNED_INT rate 10.873 Mpixels/sec
glReadPixels: ALPHA -- FLOAT rate 4.104 Mpixels/sec
glReadPixels: RED -- UNSIGNED_BYTE rate 14.438 Mpixels/sec
glReadPixels: RED -- UNSIGNED_SHORT rate 16.257 Mpixels/sec
glReadPixels: RED -- UNSIGNED_INT rate 10.741 Mpixels/sec
glReadPixels: RED -- FLOAT rate 4.108 Mpixels/sec
glReadPixels: RGB -- UNSIGNED_BYTE rate 8.770 Mpixels/sec
glReadPixels: BGR -- UNSIGNED_BYTE rate 7.352 Mpixels/sec
glReadPixels: RGBA -- UNSIGNED_BYTE rate 8.503 Mpixels/sec
glReadPixels: BGRA -- UNSIGNED_BYTE rate 7.352 Mpixels/sec
glReadPixels: RGB -- FLOAT rate 3.297 Mpixels/sec
glReadPixels: BGR -- FLOAT rate 2.651 Mpixels/sec
glReadPixels: RGB -- UNSIGNED_SHORT_5_6_5 rate 17.449 Mpixels/sec
glReadPixels: BGR -- UNSIGNED_SHORT_5_6_5 rate 336653.897 Mpixels/sec
glReadPixels: RGB -- UNSIGNED_SHORT_5_6_5_REV rate 16.416 Mpixels/sec
glReadPixels: BGR -- UNSIGNED_SHORT_5_6_5_REV rate 338937.000 Mpixels/sec
glReadPixels: RGBA -- UNSIGNED_INT_8_8_8_8 rate 7.158 Mpixels/sec
glReadPixels: BGRA -- UNSIGNED_INT_8_8_8_8 rate 7.158 Mpixels/sec
glReadPixels: RGBA -- UNSIGNED_INT_8_8_8_8_REV rate 8.461 Mpixels/sec
glReadPixels: BGRA -- UNSIGNED_INT_8_8_8_8_REV rate 7.219 Mpixels/sec

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