glPolygonMode slows down[solved]
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I have never looked into this, but just figured it was they way things are. When I render with GL_LINE my FPS drop to 1fps. Now when I was playing around with DX this never happened when rendering with lines vs. fill. What would cause such a drop? thanks
[Edited by - MARS_999 on September 13, 2006 3:14:50 PM]
When filled polyons are rendered, the graphics can use "Hierarchical Depth Buffer" and other Features to increase render speed. But when drawing lines, those components do not work.
But 1fps seems very low. When enabling this wireframe mode, I usually get 60-70% of the speed I had before on my X1800XT (don't know on Nvidia cards though).
But 1fps seems very low. When enabling this wireframe mode, I usually get 60-70% of the speed I had before on my X1800XT (don't know on Nvidia cards though).
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Quote:Original post by Enrico
When filled polyons are rendered, the graphics can use "Hierarchical Depth Buffer" and other Features to increase render speed. But when drawing lines, those components do not work.
But 1fps seems very low. When enabling this wireframe mode, I usually get 60-70% of the speed I had before on my X1800XT (don't know on Nvidia cards though).
Correct, but DX does this and I probably seen what you see and this is on a 7800GT... Only differece is GL vs. DX.
I think you mean to be using GL_LINES not GL_LINE. Unless you mistyped it here, that could be your issue. Try changing it and see if that solves the problem :)
I have observed that in general, wireframe mode is implemented by creating pixel wide triangles along the edges of the actual triangles being rendered. If you're clever you can expose this tactic through some carefully constructed geometry. In any case, it shouldn't be surprising that doing this is much slower.
Quote:What would cause such a drop?
Do you have any unusual states enabled, such a smooth lines or wide lines?
Quote:Original post by Morpheus011
I think you mean to be using GL_LINES not GL_LINE. Unless you mistyped it here, that could be your issue. Try changing it and see if that solves the problem :)
GL_LINE is the correct constant for use with glPolygonMode.
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Quote:Original post by bakery2k1Quote:What would cause such a drop?
Do you have any unusual states enabled, such a smooth lines or wide lines?Quote:Original post by Morpheus011
I think you mean to be using GL_LINES not GL_LINE. Unless you mistyped it here, that could be your issue. Try changing it and see if that solves the problem :)
GL_LINE is the correct constant for use with glPolygonMode.
Not that I know of. I do call a larger line at one point, but I never call it unless I hit a key and when in LINE mode the lines are default 1.0.
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Quote:Original post by Ravuya
The line rendering mode is very slow; I suspect it's done in software.
In GL it's software? Because with DX it was maybe 60% slow down.
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