vertex arrays

OpenGL Development
#1

So I’m trying to get some vertex array code working and it doesn’t poop and give me an error but it draws nothing (screen is grey). I’m looking at a working version and I can’t see any difference in the parts that matter.

Any idea on where the problem might be? I’m thinking my best shot at this point is just starting over. ::slight_smile:

…or sleep… or both. :wink:

#2

Well, where’s the code?

  • elias
#3

That’s a shitload of code, and it could be anywhere. I’m gonna go to sleep, and when I wake up i’ll try one more time to fix it, and if I have no success ill post the 4 billion lines. :confused:

I guess I was hoping for a “oh that” response so I could fix it before I went to sleep. I know it’s not very realistic, but I sleep like crap with programming on the brain, even falling down tired. Anyone else like that?

Seriously, I dream about it.

#4

[quote]Anyone else like that?
[/quote]
Yep. I also tend to yell loudly about the solution to bugs when I’m totally drunk… but I can’t remember the solution when i sober up :frowning: (assuming I really had a solution when I was drunk :slight_smile: )

#5

Damnit, I missed that vertex array example on the nehe/lwjgl port site when I looked the previous 2 times. Kicking myself. I thought it was just odd how that wasn’t on there so I was using a far more complicated piece of code to look at. (spgl SpriteRenderer)

I should be able to build on this slowly and see what acually breaks. Was a neat waste of 3-4 hours and a forum post though. ::slight_smile:

#6

Since I seem to be unable to convert the tex demo into a single buffer deal (hes using one for textures,colors,and indices) I decided to go my own way and go as SLOW AS POSSIBLE. I also decided even though it’s a waste of space I would just try and exactly duplicate (to the number) the first working example I ever made with a quad/texture.

So far I’m doing ok, I can see the quad, except it’s coming out completely green, and it’s one of the colors in the tile texture. So something funky is going on here:

// setup
gl.enable( GL.TEXTURE_2D );
gl.matrixMode( GL.PROJECTION );
gl.loadIdentity();
gl.glu.ortho2D( 0, width, 0, height );
gl.scalef( 1, -1, 1 );
gl.translatef( 0, -height, 0 );
gl.matrixMode( GL.MODELVIEW );
gl.loadIdentity();
gl.viewport( 0, 0, width, height );

// edit: I’m loading textures here btw :wink:

        gl.enableClientState( GL.VERTEX_ARRAY );
        gl.enable( GL.TEXTURE_2D );
        gl.bindTexture( GL.TEXTURE_2D, 7 );

// my rendering code

        MultiBuffer buf = new MultiBuffer( 80 );
        
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 16.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 16.0f );
        buf.floats.put( 16.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 16.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 1.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 1.0f );
        buf.floats.put( 1.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 1.0f );
        
        gl.loadIdentity();
        gl.translatef( 50.0f, 50.0f, 0.0f );
        
        gl.vertexPointer( 3, GL.FLOAT, 0, buf.getAddress() );
        gl.texCoordPointer( 2, GL.FLOAT, 0, buf.getAddress() + 48 );
        
        gl.drawArrays( GL.QUADS, 0, 20 );

All the MultiBuffer is doing is maintaining a ByteBuffer/IntBuffer/FloatBuffer view and getAddress() is just the Sys.getDirectBufferAddresThingy(buf). The rest of the program is completely stipped down and is just enough to get everything working.

Shoot me, please.

EDIT: ok I think I’m putting the info in the buffer wrong, i.e. you supposed to be putting the info in for each vertice(s) not the whole quad but when I change it to this I get the same result:

        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 16.0f );
        buf.floats.put( 0.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 1.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 16.0f );
        buf.floats.put( 16.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 1.0f );
        buf.floats.put( 1.0f );
        
        buf.floats.put( 0.0f );
        buf.floats.put( 16.0f );
        buf.floats.put( 0.0f );
        
        buf.floats.put( 0.0f );
        buf.floats.put( 1.0f );

        gl.vertexPointer( 3, GL.FLOAT, 20, buf.getAddress() );
        gl.texCoordPointer( 2, GL.FLOAT, 20, buf.getAddress() + 12 );
#7

…either this question is hard, or the question is really stupid. :-*

I ponder.

I think I’ll take a nap and dream of vertex arrays stabbing me in the neck slowly over and over.

#8

[quote] …either this question is hard, or the question is really stupid.
[/quote]
OR I am too drunk to answer - Neighbors & redwine = bad combo

#9

Someone get him some coffee. :wink: