Alter color during OpenGL rendering without lighting or shaders -


i need render object using existing texture, , need alter color during rendering. (such multiplying red channel 0.5.) existing texture not monochromatic. need without enabling lighting , without shaders don't disturb application i'm working within. cannot work enough in rendering read/write buffer directly.

in effect, i'd sort of color-transformation matrix or filter works during normal rendering.

base in limited information i'll assume things.

i'll assume working fixed pipeline. i'll assume not using low level pixel function glbitmap or gldrawpixels. if you should not.

to solve problem try following: draw textured quad, using glbegin,glend,glvertex2f,gltexcoord2f alter color use glcolor after glbegin , before other draw instruction. should color-transformation matrix in cpu , use result glcolor.

image blended accordingly. white doesn't change image color. make sure gl_lighting not enabled.


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