Texture vs Blending?
hi all,
it's quite simple thing i am doing here;
i read some texture (not mapped to anything yet), and left GL_TEXTURE_2D enabled;
then i try to draw some simpel points providing glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA); but the points just won't show up; until i found that if i disable GL_TEXTURE_2D before drawing the blended points....
what's the reason behind this situation?
thx all...
plus: i am using jogl
Well, I am just speculating because I'm not sure of what are you doing. There's too less information however, here are my suppositions.
You said you have used TEXTURE_2D. I understand you possibly just called TexImage and thus, bound the texture target to the object.
The fact you didn't draw textured things really does not matter. When you do
you're telling the hardware that "when something will be drawn, texture it with the current texture (object)".
Now, as far as I can remember, the default texture coordinate is (0,0). It does not really matter the exact value anyway.
My speculation is that maybe you're using a RGBA texture and fetching a texture color which is (?,?,?,0). Since default texture env function is MODULATE, you end up with all transparent fragments.
Another idea may be to fetch (0,0,0,?) on a black background so they don't show up anyway.
Maybe provide some additional information.
PS: please check your private messages.
You said you have used TEXTURE_2D. I understand you possibly just called TexImage and thus, bound the texture target to the object.
The fact you didn't draw textured things really does not matter. When you do
glEnable(GL_TEXTURE_2D);
you're telling the hardware that "when something will be drawn, texture it with the current texture (object)".
Now, as far as I can remember, the default texture coordinate is (0,0). It does not really matter the exact value anyway.
My speculation is that maybe you're using a RGBA texture and fetching a texture color which is (?,?,?,0). Since default texture env function is MODULATE, you end up with all transparent fragments.
Another idea may be to fetch (0,0,0,?) on a black background so they don't show up anyway.
Maybe provide some additional information.
PS: please check your private messages.
Previously "Krohm"
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