50 lines
1.6 KiB
Text
50 lines
1.6 KiB
Text
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DESCRIPTION OF PROBLEM:
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=======================
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The example map, maps/disappearing_sliver3.map, contains an example of this
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bug. The triangle sliver surface in the middle of the room is not rendered
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in the final BSP.
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To trigger the bug, compile the map; you don't need -vis or -light. Only
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-bsp (the first q3map2 stage) is necessary to trigger the bug. The only
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entities in the map are a light and a info_player_deathmatch, so the map will
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compile for any Q3 mod.
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SOLUTION TO PROBLEM:
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====================
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More work has been done to BaseWindingForPlane() to make it more accurate.
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This function is in polylib.c. The changes to fix this regression test were
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committed in revision 377; however, those changes are not "good enough".
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IN-DEPTH DISCUSSION:
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====================
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This is the problem triangle:
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In ParseRawBrush() for brush 0
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Side 0:
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(6144.000000 16122.000000 -2048.000000)
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(6144.000000 16083.000000 -2048.000000)
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(6784.000000 16241.000000 -2048.000000)
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Computed winding before fix:
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(6784.16406250 16241.04101562 -2048.00000000)
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(6144.00000000 16122.00976562 -2048.00000000)
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(6144.00000000 16083.00000000 -2048.00000000)
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Obviously the 6784.16406250 is beyond epsilon error.
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After revision 377:
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(6783.85937500 16240.96484375 -2048.00000000)
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(6144.00000000 16121.99218750 -2048.00000000)
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(6144.00000000 16083.00000000 -2048.00000000)
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Even though this fixes the regression test, the error in 6783.85937500 is
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still greater than epsilon (but fortunately in the opposite direction). So
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I don't consider this test case to be fixed quite yet.
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