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C-/C++-Quelltext

long DrawPrimitiveUP (::D3DPRIMITIVETYPE type, unsigned long count, const void *data, unsigned long stride, ::IDirect3DDevice9* device)
{
        // Rückgabewert

    long result = D3D_OK;

        // Device muß vorhanden sein!

    if (!device) return (E_FAIL);

        // Vertexbuffer

    ::IDirect3DVertexBuffer9 *vertexbuffer = NULL;

        // Vertexbuffer erstellen

    if ((result = device->CreateVertexBuffer (stride*count, D3DUSAGE_WRITEONLY, 0, D3DPOOL_DEFAULT, &vertexbuffer, NULL)) != D3D_OK)
        return (result);

        // Pointer auf Datenbereich

    void *vertices = NULL;

        // Verriegeln ist angesagt!

    if ((result = vertexbuffer->Lock (0, 0, &vertices, 0)) != D3D_OK)
        return (result);

        // Vertices kopieren (Secure Rocks!)

    if (::memcpy_s (vertices, stride*count, data, stride*count) != 0)
        return (E_FAIL);

        // Entriegeln

    if ((result = vertexbuffer->Unlock ()) != D3D_OK)
        return (result);

        // Verbindung zwischen Vertexbuffer und Renderingstream herstellen

    if ((result = device->SetStreamSource (0, vertexbuffer, 0, stride)) != D3D_OK)
        return (result);

        // Rendern

    if ((result = device->DrawPrimitive (type, 0, count)) != D3D_OK)
        return (result);

        // VertexBuffer freigeben NIEMALS vergessen!

    if (vertexbuffer != NULL)
    {
        vertexbuffer->Release ();
        vertexbuffer = NULL;
    }

        // Alles roger!

    return (result);
}

C-/C++-Quelltext

void triangle (const vertex &v1, const vertex &v2, const vertex &v3)
{
        // Y-Positionen der Dreiecke merken

    const float x1 = v1.x;
    const float x2 = v2.x;
    const float x3 = v3.x;

        // X-Positionen der Dreiecke merken

    const float y1 = v1.y;
    const float y2 = v2.y;
    const float y3 = v3.y;

        // Bounding Rechteck Dimensionen bestimmen

    const long minx = static_cast<long>(min(x1, x2, x3));
    const long maxx = static_cast<long>(max(x1, x2, x3));
    const long miny = static_cast<long>(min(y1, y2, y3));
    const long maxy = static_cast<long>(max(y1, y2, y3));

        // Startpunkt setzen

    reinterpret_cast<char*>(&backbuffer) += miny * pitch;

        // Das Bounding Rechteck durchlaufen

    for (long y=miny; y<maxy; ++y)
    {
        for (long x=minx; x<maxx; ++x)
        {
                // Prüfen ob Pixel _im_ Dreieck liegt

            if ((x1 - x2) * (y - y1) - (y1 - y2) * (x - x1) > 0 &&
             << (x2 - x3) * (y - y2) - (y2 - y3) * (x - x2) > 0 &&
             << (x3 - x1) * (y - y3) - (y3 - y1) * (x - x3) > 0)
            {
                    // Weißen Pixel malen

                backbuffer[x] = 0xFFFFFFFF;
            }
        }

            // Startpunkt neu setzen

        reinterpret_cast<char*>(&backbuffer) += pitch;
    }
}