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Dark Adept

Allegro Blender Function Ignored

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Hi. I'm working on a 3D engine using Allegro. I'm using the set_multiply_blender() function to shade my textured polygons, but I'm having some trouble. When I run my program using Allegro's z-buffer, I have no problems. My shaded polygons (textured or otherwise) come out looking fine. However, if I use Allegro's scanline algorithm (eg. create_scene, clear_scene, scene_polygon3d, etc.), the parameters in the blender function appear to be ignored. What's going on? I've been at this for hours.
if (rendering_mode == RM_SCANLINE) {
        for (i = 0; i < 6; i++) {
            p = &point;
            ptmp = &tmp;
            p->c = 255;

        num_v = clip3d_f(POLYTYPE_PTEX_LIT, 0., 1000., 3,
                        (AL_CONST V3D_f**)p, p, ptmp, out);
        for (i = 0; i < num_v; i++) {
            persp_project_f(p->x, p->y, p->z,
                          &p->x, &p->y);
            p->y = SCR_HEIGHT - p->y;

        set_multiply_blender (r, g, b, 255);
        scene_polygon3d_f(POLYTYPE_PTEX_LIT, pic[tex], num_v, p);

The business section is the two lines at the end. r, g, and b are what I want to multiply the colours on the polygon by. Anything you guys could tell me would be great. Thanks in advance. Edit: Figured out how to use the source tags

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