instead of blending, you can do an alphatest… then you have your alphacomponetns filtered anyways, but it dont use the equation AB+CD wich results in halftransparent parts of the pixels, but it uses if alpha (EQUAL,LOWER,etc) a static value, the pixel is rendered or not… (results in more than pixel detailed transparence when it is billinear filtered… looks cool in my opinion)
The alpha comparison function. The following are the accepted symbolic constants and their meanings. Symbolic Constant Meaning
GL_NEVER Never passes.
GL_LESS Passes if the incoming alpha value is less than the reference value.
GL_EQUAL Passes if the incoming alpha value is equal to the reference value.
GL_LEQUAL Passes if the incoming alpha value is less than or equal to the reference value.
GL_GREATER Passes if the incoming alpha value is greater than the reference value.
GL_NOTEQUAL Passes if the incoming alpha value is not equal to the reference value.
GL_GEQUAL Passes if the incoming alpha value is greater than or equal to the reference value.
GL_ALWAYS Always passes. This is the default.
The reference value to which incoming alpha values are compared. This value is clamped to the range 0 through 1, where 0 represents the lowest possible alpha value and 1 the highest possible value. The default reference is 0.
The alpha test discards fragments depending on the outcome of a comparison between the incoming fragments’ alpha values and a constant reference value. The glAlphaFunc function specifies the reference and comparison function. The comparison is performed only if alpha testing is enabled. (For more information on GL_ALPHA_TEST, see glEnable.)
The func and ref parameters specify the conditions under which the pixel is drawn. The incoming alpha value is compared to ref using the function specified by func. If the comparison passes, the incoming fragment is drawn, conditional on subsequent stencil and depth-buffer tests. If the comparison fails, no change is made to the frame buffer at that pixel location.
The glAlphaFunc function operates on all pixel writes, including those resulting from the scan conversion of points, lines, polygons, and bitmaps, and from pixel draw and copy operations. The glAlphaFunc function does not affect screen clear operations.
Alpha testing is done only in RGBA mode.