OpenGL with vertex arrays

[N64vSNES]

EDIT:
See newest post...

[Nokurn]

I can't seem to find an answer for this so hopefully you guys could help.

Suppose I have a 32x32 texture and a 64x64 quad. Now if I render this then the texture gets "stretched" as you would imagine because you've specified the texture coords where the vertices are.

I'm fairly sure that using GL_REPEAT would do this IF I go past 1.0 with the texture coords however this isn't much using part of a texture atlas.

Any advice?

Thanks.

I am not quite sure what you are asking here. There is no question, and it looks like there's supposed to be a sentence between the second and third. If you could rephrase, someone might be able to provide some insight.

[Falco Girgis]

I can't seem to find an answer for this so hopefully you guys could help.

Suppose I have a 32x32 texture and a 64x64 quad. Now if I render this then the texture gets "stretched" as you would imagine because you've specified the texture coords where the vertices are.

I'm fairly sure that using GL_REPEAT would do this IF I go past 1.0 with the texture coords however this isn't much using part of a texture atlas.

Any advice?

Thanks.

I am not quite sure what you are asking here. There is no question, and it looks like there's supposed to be a sentence between the second and third. If you could rephrase, someone might be able to provide some insight.

That's exactly what I was going to say.

You never asked us a question.

[N64vSNES]

Yes I see where I went wrong there
I'll start from the beginning

Suppose this is my texture:


I want to use this texture on a quad like this:


I could break the quad into 4 different quads but then I'm losing performance.


Short and simple as possible

[qpHalcy0n]

This can not be done as you describe within the fixed function. Sorry.

The texture or the geometry must be split or you must write the functionality into a shader program.

[N64vSNES]

This can not be done as you describe within the fixed function. Sorry.

The texture or the geometry must be split or you must write the functionality into a shader program.

Well this is going to cause problems

Thanks for the help though.

[Falco Girgis]

This can not be done as you describe within the fixed function. Sorry.

The texture or the geometry must be split or you must write the functionality into a shader program.

Well this is going to cause problems

Thanks for the help though.

I'm guessing you're just trying to optimize some shit? ...you could always pick up shaders.

[N64vSNES]

This can not be done as you describe within the fixed function. Sorry.

The texture or the geometry must be split or you must write the functionality into a shader program.

Well this is going to cause problems

Thanks for the help though.

I'm guessing you're just trying to optimize some shit? ...you could always pick up shaders.

Yep. The only alternative would be dropping the whole texture atlas buissness but then I doubt I'd gain much performance having to switch textures. in fact, I might even make it slower that way

I'll look into shaders...Probably won't end pretty xD

[qpHalcy0n]

...or you could just split up the geometry. You know that the vertex transformation pipeline is extremely optimized and that you should have no problem pushing dozens of thousands and thousands and thousands of polys through it.

[N64vSNES]

...or you could just split up the geometry. You know that the vertex transformation pipeline is extremely optimized and that you should have no problem pushing dozens of thousands and thousands and thousands of polys through it.

Vertex transformation pipeline, optimized. I was about to say the same thing!

[N64vSNES]

I decided to edit this topic since I didn't want to spam the forum with tedious questions like this.

So I finally took qpHalcy0n's advice...Or reality slap and actually implemented a vertex array for Crafter. (Yes I was stupid enough to render the entire map with the immediate pipeline)

Now it works and perfectly with a much higher poly count as expected. But I did hit a problem with the textures.

Now here is how I render the map:

Code: Select all

		glEnable(GL_TEXTURE_2D);
		glBindTexture(GL_TEXTURE_2D,t_BlockSet.GetTex());
		glColor3f(1,1,1);
		glEnableClientState(GL_VERTEX_ARRAY);
		glEnableClientState(GL_TEXTURE_COORD_ARRAY);

		glVertexPointer(3, GL_FLOAT, 0, &Verts[0].x);
		glTexCoordPointer(2,GL_FLOAT, 0, &TexChoords[0].x);

		glDrawArrays(GL_QUADS,0,i_FacesDrawn * 4);

		glDisableClientState(GL_TEXTURE_COORD_ARRAY);
		glDisableClientState(GL_VERTEX_ARRAY);

The map renders correctly, but the textures are pretty screwed:


So, help?

The texture coords are definitely correct, there are a equal number of vertices as there are texture coords, all the basic stuff seems fine.

Am I missing something obvious?

[Ginto8]

It looks like some of the edges are slanted, so you might not be feeding some vertices into the pipeline that you should be, or you're feeding them in incorrectly.
The only thing that could make those kinds of texture errors, to my knowledge, is wrong texture coordinates

[TheBuzzSaw]

Did you switch to indexed rendering? Or are you still repeating vertices?