way to give certain colors alpha value in textures

Hi, I am trying to give my game a less square look but if textures get loaded as squares how do I go about haveing curverd edges. Should I be giving a certain color in the texture a alpha value like pink or something? If so how?

What does that mean? Is this a 2D game? A 3D game? Are you saying you want your sprites to look more rounded? Or you want to get rid of jagged geometry so the contours of your shape are more like smooth curves instead of polygons?

In OpenGL one renders geometry and if that happens to be mapped to a texture, that part of the geometry will have that color. Textures are usual rectangular and the geometry will map out parts of that to get color and/or alpha value.

If you render a box in 3D with six sides, it’s going to look square no matter how to texture it. If you want something more rounded and beveled, you have to apply that to your model as geometry. Texturing isn’t going to fix that.