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Blending&textures problem.

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I'm creating a 2D game and I want to use some transparent sprites, but the blending doesn't work for me the way I want it to work. I've made a 2x2 texture to test it. CODE! texlist[1]:=255; //1 R texlist[2]:=0; /// 1 G texlist[3]:=0; /// 1 B texlist[4]:=255; //1 A texlist[5]:=0; /// 2 R texlist[6]:=255; //2 G texlist[7]:=0; /// 2 B texlist[8]:=255; //2 A texlist[9]:=0; /// 3 R texlist[10]:=0; // 3 G texlist[11]:=255;//3 B texlist[12]:=255;//3 A texlist[13]:=255;//4 R texlist[14]:=0; // 4 G texlist[15]:=255;//4 B texlist[16]:=0; // 4 A gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGBA, 2,2, GL_RGBA, GL_BYTE, @texlist); END OF CODE! The output was 1 on this pic: http://img222.imageshack.us/img222/2118/rgbajm9.jpg But I want it to work as shown on second pic - I want the entire transparent pixel not to be visible. I've been trying almost everything. The key is probably the glAlphaFunc or glBlendFunc glEnable(GL_ALPHA_TEST); glAlphaFunc(GL_GREATER, 0.5); // modyfying this value changes the radius of that transparent circle. glBlendFunc(GL_ONE,GL_ONE); glEnable(GL_BLEND); additional pic http://img233.imageshack.us/img233/8564/50869792ov3.jpg

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glBlendFunc... try glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
There are many more possible combinations for this, but the one I just gave works well for standard transparency.

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It didn't change anything. I have later figured that blending doesn't matter here anyway.

But well I have changed glAlphaFunc(GL_GREATER, 0.8); to 0.8 as it has given best results and loaded some sprites. Take a look.


My looks like pasted in paint :|. How do I make it so that edges blends or w/e is happening there

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I got some better results using

//glAlphaFunc(GL_GREATER, 0.1);
I didn't know that turning alpha test off may improve this :P


But now anyone knows how to get rid of those lines?

Edit. Where can I get newer OpenGL libraries for Delphi?
coz ... [Error] main.pas(114): E2003 Undeclared identifier: 'GL_MIRRORED_REPEAT'

[Edited by - Enderdil on September 30, 2007 7:35:20 AM]

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Those are most likely edge artifacts from the texture/sprite itself. Have you checked the sprite images themselves to assert that the edges of them are clean? If they are, then its some GL border issue or such, and I'm drawing a blank.

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Sprites are 100% fine, but OpenGL tries to repeat those textures probably. I've managed to disable repeating by
but then other textures looks worse (eg. ground sprites)
I thought that solution for this would be adding a property for each texture telling to CLAMP or to REPEAT but what if my sprite looks like that!
Notice the lines at the top and bottom on the repeating one.

I've been thinking on creating textures using:
then drawing everything I want
and then SMOTHING THE ENTIRE SCREEN just like textures are being smothed when using
Is there any easy way (glEnable ?) or would I have to copy the screen as a testure and draw it on one quad on the screen ?

[Edited by - Enderdil on September 30, 2007 4:54:17 PM]

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