Sprite Sheet With OpenGL and SDL

I been working in a new game, and finally reached the point where I started to code the motion of my main character but I have a doubt about how do that.

Previously, I make two games in Allegro, so the spritesheets are kind of easy to implement, because I establish the frame and position on the image, and 开发者_Python百科save every frame in a different bitmap, but I know that do that with OpenGL it's not neccesary and cost a little bit more.

So, I been thinking in how save my spritesheet and used in my program and I have only one idea.

I loaded the image and transformed in a texture, in my function that help me animate I simply grab a portion of the texture to draw instead of store every single texture in my program.

This is the best way to do that?

Thanks beforehand for the help.

You're on the right track.

Things to consider:

• leave enough dead space around each sprite so that the video card does not blend in texels from adjacent sprites at small scales.
• set texture min/mag filtering appropriately. GL_NEAREST is OK if you're going for the blocky look.
• if you want to be fancy and save some texture memory, there's no reason that the sprites have to be laid out in a regular grid. Smaller sprites can be packed closer in the texture.
• if your sprites are being rendered from 3D models, you could output normal & displacement maps from the model into another texture, then combine them in a fragment shader for some awesome lighting and self-shadowing.

You got the right idea, if you have a bunch of sprites it is much better to just stick them all in one big textures. Just draw your sprites as textured quads whose texture coordinates index into the frame of the sprite. You can do a few optimizations, but most of them revolve around trying to get the most out of your texture memory and packing the sprites closely together with out blending issues.

I know that do that with OpenGL it's not neccesary and cost a little bit more.

Why not? There are no real downsides to putting a lot of sprites into a single texture. All you need to do is change the texture coordinates to pick the region in question out of the texture.