flattexalphazc.h

Go to the documentation of this file.

inline void LeRasterizer::fillFlatTexAlphaZC(int y, int x1, int x2, int w1, int w2, int u1, int u2, int v1, int v2)
{
    uint8_t * sc = (uint8_t *) &curTriangle->solidColor;

    int d = x2 - x1;
    if (d == 0) return;

    int au = (u2 - u1) / d;
    int av = (v2 - v1) / d;
    int aw = (w2 - w1) / d;

    if (++x2 > frame.tx) x2 = frame.tx;
    uint8_t * p = (uint8_t *) (x1 + y * frame.tx + pixels);

    for (int x = x1; x < x2; x++) {
        int32_t z = (1 << 30) / (w1 >> 8);
        uint32_t tu = (((int64_t) u1 * z) >> 24) & texMaskU;
        uint32_t tv = (((int64_t) v1 * z) >> 24) & texMaskV;
        uint8_t * t = (uint8_t *) &texDiffusePixels[tu + (tv << texSizeU)];

        uint16_t a = 256 - t[3];
        p[0] = (p[0] * a + t[0] * sc[0]) >> 8;
        p[1] = (p[1] * a + t[1] * sc[1]) >> 8;
        p[2] = (p[2] * a + t[2] * sc[2]) >> 8;
        p += 4;

        u1 += au;
        v1 += av;
        w1 += aw;
    }
}