Drawing a 2D texture in OpenGL [closed]

Answer 1

If you're ok with using OpenGL 3.0 or higher, an easier way to draw a texture is glBlitFramebuffer(). It won't support rotation, but only copying the texture to a rectangle within your framebuffer, including scaling if necessary.

I haven't tested this code, but it would look something like this, with tex being your texture id:

GLuint readFboId = 0;
glGenFramebuffers(1, &readFboId);
glBindFramebuffer(GL_READ_FRAMEBUFFER, readFboId);
glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
                       GL_TEXTURE_2D, tex, 0);
glBlitFramebuffer(0, 0, texWidth, texHeight,
                  0, 0, winWidth, winHeight,
                  GL_COLOR_BUFFER_BIT, GL_LINEAR);
glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
glDeleteFramebuffers(1, &readFboId);

You can of course reuse the same FBO if you want to draw textures repeatedly. I only create/destroy it here to make the code self-contained.