Color- and texture-anomalities when using Vertex Buffers.

[Bvsemmer]

Hi list,

I'm having trouble adding color and texture-coordinates to my vertices in a Vertex Buffer.  I use this to fill my colorbuffer and put them into a Vertex Buffer (like I do for the vertices and indices) :

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colorbuffer = BufferUtils.createFloatBuffer(4 * 4); colorbuffer.put(255).put(0).put(0).put(255); colorbuffer.put(255).put(0).put(0).put(255); colorbuffer.put(255).put(0).put(0).put(255); colorbuffer.put(255).put(0).put(0).put(255); colorbuffer.flip(); ARBVertexBufferObject.glBindBufferARB(ARBVertexBufferObject.GL_COLOR_ARRAY_BUFFER_BINDING_ARB, colorbufferID); ARBVertexBufferObject.glBufferDataARB(ARBVertexBufferObject.GL_COLOR_ARRAY_BUFFER_BINDING_ARB, colorbuffer, ARBVertexBufferObject.GL_STATIC_DRAW_ARB);

This gives the following compile error:
"Unsupported VBO target 34970"

I'm pretty sure I know what this means, but what kind of buffer should I use then?  Perhaps I'm doing something terribly wrong?

If I use the GL_ARRAY_BUFFER_ARB flag, everything seems to work:

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ARBVertexBufferObject.glBindBufferARB(ARBVertexBufferObject.GL_ARRAY_BUFFER_ARB, colorbufferID); ARBVertexBufferObject.glBufferDataARB(ARBVertexBufferObject.GL_ARRAY_BUFFER_ARB, colorbuffer, ARBVertexBufferObject.GL_STATIC_DRAW_ARB);

...but then I'm overwriting my vertex buffer ofcourse. 
How can I avoid this please?  What is the correct way to use this?

Thank you!

[Riven]

You're not overriding your vertex data this way (or at least: shouldn't be)

it's like this:

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bindBuffer(..., x) bufferData(..., dataX, ...) bindBuffer(..., y) bufferData(..., dataY, ...)

now buffer x holds dataX
now buffer y holds dataY

[Riven]

According to your topic-title, you see artifacts.

This happens when your VBO has less elements than required.
like if vertex-array has 12 elements and color-array has 9 elements... the last 3 elements will be garbage colors

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[anarchotron]

One problem I see with this is that you are specifying your color buffer as a FloatBuffer, but specifying your colors as 255,0,0,255 (red, presumably).  The valid range of a float color component is [0..1].  Try using 1.0f instead of 255.  It may look ok because the values are being clamped to the proper range for you.

At any rate, the GL_ARRAY_BUFFER_ARB usage you mentioned secondly is the correct usage, not GL_COLOR_ARRAY_BUFFER_BINDING_ARB.  Why do you think this is incorrect?  (Maybe I'm misuing my VBOs but I use G_ARRAY_BUFFER_ARB to create & load my vbos with data).

[Bvsemmer]

You're not overriding your vertex data this way (or at least: shouldn't be)

Thank you, that was indeed my problem (stupid mistake, if you think about it ).  Everything works like a charm now. 

At any rate, the GL_ARRAY_BUFFER_ARB usage you mentioned secondly is the correct usage, not GL_COLOR_ARRAY_BUFFER_BINDING_ARB. Why do you think this is incorrect?

I guess I was a bit confused with the "glEnableClientState()"-method where they explicitly use different states, like "GL11.GL_TEXTURE_COORD_ARRAY" and "GL11.GL_COLOR_ARRAY".

Thanks again for the help!