OpenGL Sprites

[Moosader]

So, as some peoples know, I'm attempting to remake ET in OpenGL and SDL. o_o
Instead of having 3D models or anything for ET and the baddies, I want to have flat 2D sprites like this:



I know how to load textures, but I don't know how to set a certain area to transparent. Do I need to figure out how to check each pixel on a texture and replace, say, (1.0, 0.0, 1.0) with ... nothingness. 0.o;
I don't know. I assume there's a function in OpenGL to turn an image partially or fully transparent, and I just need to do that for the appropriate pixels.

[eatcomics]

Oh look, a Gay Pride Square!!! those are growing indangered...

[Falco Girgis]

. . . I have a certain fondness for that square.

The way we did it was really easy. Our PNG library: glpng handles transparencies itself. You just load it as being a transparent PNG. That's what I recommend you look into, because I'm not a big fan of hardcoding transparencies.

[Moosader]

Ah, sounds good then!

And yep, I colored it like a gay pride square on purpose. :D

[MarauderIIC]

You can also do masking.

And you can use an 'alpha channel'

[Moosader]

. . . I have a certain fondness for that square.

The way we did it was really easy. Our PNG library: glpng handles transparencies itself. You just load it as being a transparent PNG. That's what I recommend you look into, because I'm not a big fan of hardcoding transparencies.

About GLPNG -- It requires GLUT as well? So are you using OpenGL, SDL, AND GLUT for the game?

[marmalade]

:guffaw: The gay pride square, I remember someone commenting in one of the earlier Adventures in Game Development videos about that.

As for the question, I have no idea. I'm too horrible at programming to even think of coding in OpenGL.

I am not worthy!

[cypher1554R]

I'm not sure.. can you load a .png format texture (which contains alpha values) and setup the program for alpha blending to achieve that..?

PS: As far as I know you can't geometrically modify the texture..