Checks that ReadPixels works as expected.

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".


checking: in range
PASS color pixel at 0, 0 should be about 127.5
PASS color pixel at 0, 0 should be about 178.5
PASS color pixel at 0, 0 should be about 255
PASS color pixel at 0, 0 should be about 255
PASS color pixel at 1, 0 should be about 127.5
PASS color pixel at 1, 0 should be about 178.5
PASS color pixel at 1, 0 should be about 255
PASS color pixel at 1, 0 should be about 255
PASS color pixel at 0, 1 should be about 127.5
PASS color pixel at 0, 1 should be about 178.5
PASS color pixel at 0, 1 should be about 255
PASS color pixel at 0, 1 should be about 255
PASS color pixel at 1, 1 should be about 127.5
PASS color pixel at 1, 1 should be about 178.5
PASS color pixel at 1, 1 should be about 255
PASS color pixel at 1, 1 should be about 255

checking: off top left
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 1, 1 should be about 127.5
PASS color pixel at 1, 1 should be about 178.5
PASS color pixel at 1, 1 should be about 255
PASS color pixel at 1, 1 should be about 255

checking: off bottom right
PASS color pixel at 0, 0 should be about 127.5
PASS color pixel at 0, 0 should be about 178.5
PASS color pixel at 0, 0 should be about 255
PASS color pixel at 0, 0 should be about 255
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0

checking: completely off top 
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0

checking: completely off bottom
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0

checking: completely off left
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0

checking: completeley off right
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 0, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 1, 0 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 0, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS color pixel at 1, 1 should be about 0
PASS getError was expected value: NO_ERROR : there should be no GL errors

check disallowed formats
PASS getError was expected value: INVALID_OPERATION : Should not be able to read as RGB / UNSIGNED_BYTE
PASS getError was expected value: INVALID_OPERATION : Should not be able to read as RGB / UNSIGNED_SHORT_5_6_5
PASS getError was expected value: INVALID_OPERATION : Should not be able to read as RGBA / UNSIGNED_SHORT_5_5_5_1
PASS getError was expected value: INVALID_OPERATION : Should not be able to read as RGBA / UNSIGNED_SHORT_4_4_4_4
PASS getError was expected value: INVALID_OPERATION : Should not be able to read as ALPHA / UNSIGNED_BYTE
PASS getError was expected value: INVALID_ENUM : Should not be able to read as LUMINANCE / UNSIGNED_BYTE
PASS getError was expected value: INVALID_ENUM : Should not be able to read as LUMINANCE_ALPHA / UNSIGNED_BYTE

check reading with lots of drawing
PASS actual is expected
PASS actual is expected
PASS actual is expected
PASS getError was expected value: NO_ERROR : there should be no GL errors

PASS successfullyParsed is true

TEST COMPLETE