I was wondering if there is a way to create let’s say 1px outline around a transparent (PNG) texture that is mapped on opengl quad. I’m using 32-bit png images. Is it possible without using shaders?
It is possible, the idea is to render the sprite with a GLSL fragment shader doing something resembling a blur filter, then store the result in a texture.
Without shaders, it can be done for example by doing jittered passes to fill a stencil buffer, then render red quad to pass only on some values of stencil.
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