When you scale an image, say 308x193, does it have to be to the closest power of 2, or do you scale both of them up to the next power of 2?
Edit:: So should the scaled size be 256x256 or 512x256?
Edit2:: Or does it not matter as long as you scale them both the same way?
[Edited by - Endar on November 7, 2005 12:36:42 AM]
md2 texturing
Quote:Original post by Endar
When you scale an image, say 308x193, does it have to be to the closest power of 2, or do you scale both of them up to the next power of 2?
Edit:: So should the scaled size be 256x256 or 512x256?
Edit2:: Or does it not matter as long as you scale them both the same way?
I think it doesn't matter.
Btw try to flip your texture horizontally or vertically and both. I had this problem also, untill I figured to set the UV coordinates correctly.
Author
Okay, so, currently, I'm scaling them both up.
How do I flip the texture? Do I actually use a gl call, or is this something like just doing:
Does this flip it both horizontally and vertically?
How do I flip the texture? Do I actually use a gl call, or is this something like just doing:
m_vertexList.u = 1 - ((float)stPtr.s / (float)width);m_vertexList.v = 1 - ((float)stPtr.t / (float)height);Does this flip it both horizontally and vertically?
Quote:Original post by Endar
Okay, so, currently, I'm scaling them both up.
How do I flip the texture? Do I actually use a gl call, or is this something like just doing:m_vertexList.u = 1 - ((float)stPtr.s / (float)width);m_vertexList.v = 1 - ((float)stPtr.t / (float)height);
Does this flip it both horizontally and vertically?
I think that works, yes. You can also try to flip it in an image-editing application.
I have this for my md2 loader
the ReadShort are s and t accordingly.
header.skinwidth and header.skinheight are dimention of the texture in pixels
the ReadShort are s and t accordingly.
header.skinwidth and header.skinheight are dimention of the texture in pixels
//un compress them to temp array kbo.u = (float)ReadShort(&file) / header.skinwidth; kbo.v = (float)ReadShort(&file) / header.skinheight - 1;//and now I put them into ready to use form for(i = 0; i < header.num_face; i++) { // A side tbo[cnt].u = kbo[fbo.auv].u; tbo[cnt++].v = kbo[fbo.auv].v; // B side tbo[cnt].u = kbo[fbo.buv].u; tbo[cnt++].v = kbo[fbo.buv].v; // C side tbo[cnt].u = kbo[fbo.cuv].u; tbo[cnt++].v = kbo[fbo.cuv].v; }
Author
Quote:Original post by DMINATOR
header.skinwidth and header.skinheight are dimention of the texture in pixels
The size after the texture has been scaled, or the size before the texture has been scaled?
it is size in pixels the texture has. If you scale texture proportionally then it doesn't matter.
-DMINATOR
-DMINATOR
The MD2 file has the texture coords in range 0-1 or 0 - texturesize ?
The texture coordinates don't have too much to do with the actual texture size in OpenGl (or DX). That is, I can use high detail textures or low resolution textures without touching the texture coordinates.
I can imagine that scaling the coords screw up the texturing.
Author
Okay, well, I'm no longer scaling the actual coords that I'm using to calculate the coords from the shorts.
Here is what it currently looks like, and I've tried flipping the texture using the "1 - " at the beginning of the u and v calculations, tried both individually, at the same time, and none, and I'm always getting similar variations on what is in the picture.
Here is what it currently looks like, and I've tried flipping the texture using the "1 - " at the beginning of the u and v calculations, tried both individually, at the same time, and none, and I'm always getting similar variations on what is in the picture.
This topic is closed to new replies.
Advertisement
Popular Topics
Advertisement
