void renderTriangles(const SPVertex * _pVertices, const GLubyte * _pElements, u32 _numElements)
{
//Current depth buffer can be null if we are loading from a save state
if(depthBufferList().getCurrent() == nullptr)
return;
vertexclip vclip[16];
vertexi vdraw[12];
const SPVertex * vsrc[4];
SPVertex vdata[6];
for (u32 i = 0; i < _numElements; i += 3) {
u32 orbits = 0;
if (_pElements != nullptr) {
for (u32 j = 0; j < 3; ++j) {
vsrc[j] = &_pVertices[_pElements[i + j]];
orbits |= vsrc[j]->clip;
}
} else {
for (u32 j = 0; j < 3; ++j) {
vsrc[j] = &_pVertices[i + j];
orbits |= vsrc[j]->clip;
}
}
vsrc[3] = vsrc[0];
int numVertex = clipW(vsrc, vdata);
if (!calcScreenCoordinates(vdata, vclip, numVertex))
continue;
const int dzdx = ((orbits & CLIP_W) == 0) ? calcDzDx(vclip) : calcDzDx2(vsrc);
if (dzdx == 0)
continue;
if (orbits == 0) {
assert(numVertex == 3);
if ((gSP.geometryMode & G_CULL_BACK) != 0) {
for (int k = 0; k < 3; ++k) {
vdraw[k].x = floatToFixed16(vclip[k].x);
vdraw[k].y = floatToFixed16(vclip[k].y);
vdraw[k].z = floatToFixed16(vclip[k].z);
}
} else {
for (int k = 0; k < 3; ++k) {
const u32 idx = 3 - k - 1;
vdraw[k].x = floatToFixed16(vclip[idx].x);
vdraw[k].y = floatToFixed16(vclip[idx].y);
vdraw[k].z = floatToFixed16(vclip[idx].z);
}
}
} else {
vertexclip ** vtx;
numVertex = ClipPolygon(&vtx, vclip, numVertex);
if (numVertex < 3)
continue;
if ((gSP.geometryMode & G_CULL_BACK) != 0) {
for (int k = 0; k < numVertex; ++k) {
vdraw[k].x = floatToFixed16(vtx[k]->x);
vdraw[k].y = floatToFixed16(vtx[k]->y);
vdraw[k].z = floatToFixed16(vtx[k]->z);
}
} else {
for (int k = 0; k < numVertex; ++k) {
const u32 idx = numVertex - k - 1;
vdraw[k].x = floatToFixed16(vtx[idx]->x);
vdraw[k].y = floatToFixed16(vtx[idx]->y);
vdraw[k].z = floatToFixed16(vtx[idx]->z);
}
}
}
Rasterize(vdraw, numVertex, dzdx);
}
}
void scanConverter(GzRender *render, GzCoord *vertexList)
{
GzCoord top, mid, btm;
GzCoord vtx1, vtx2, vtx3;
/* Find a bounding box of the tri, and sort 3 verts */
/* Find max and min x values */
float minx, miny, maxx, maxy;
if (vertexList[0][0] >= vertexList[1][0])
{
maxx = vertexList[0][0];
minx = vertexList[1][0];
}
else
{
maxx = vertexList[1][0];
minx = vertexList[0][0];
}
if (vertexList[2][0] > maxx) maxx = vertexList[2][0];
if (vertexList[2][0] < minx) minx = vertexList[2][0];
/* Find max and min y values*/
if (vertexList[0][1] >= vertexList[1][1])
{
top[0] = vertexList[0][0]; top[1] = vertexList[0][1]; top[2] = vertexList[0][2];
btm[0] = vertexList[1][0]; btm[1] = vertexList[1][1]; btm[2] = vertexList[1][2];
}
else
{
top[0] = vertexList[1][0]; top[1] = vertexList[1][1]; top[2] = vertexList[1][2];
btm[0] = vertexList[0][0]; btm[1] = vertexList[0][1]; btm[2] = vertexList[0][2];
}
if (vertexList[2][1] > top[1])
{
mid[0] = top[0]; mid[1] = top[1]; mid[2] = top[2];
top[0] = vertexList[2][0]; top[1] = vertexList[2][1]; top[2] = vertexList[2][2];
}
else if (vertexList[2][1] < btm[1])
{
mid[0] = btm[0]; mid[1] = btm[1]; mid[2] = btm[2];
btm[0] = vertexList[2][0]; btm[1] = vertexList[2][1]; btm[2] = vertexList[2][2];
}
else
{
mid[0] = vertexList[2][0]; mid[1] = vertexList[2][1]; mid[2] = vertexList[2][2];
}
maxx = ceil(maxx);
maxy = ceil(top[1]);
minx = floor(minx);
miny = floor(btm[1]);
if (top[1] == mid[1]) // Top edge exits
{
if (top[0] < mid[0])
{
vtx1[0] = top[0]; vtx1[1] = top[1]; vtx1[2] = top[2];
vtx2[0] = mid[0]; vtx2[1] = mid[1]; vtx2[2] = mid[2];
}
else
{
vtx2[0] = top[0]; vtx2[1] = top[1]; vtx2[2] = top[2];
vtx1[0] = mid[0]; vtx1[1] = mid[1]; vtx1[2] = mid[2];
}
vtx3[0] = top[0]; vtx1[1] = top[1]; vtx1[2] = top[2];
}
else if (btm[1] == mid[1]) // Bottom edge exits
{
if (btm[0] < mid[0])
{
vtx3[0] = btm[0]; vtx3[1] = btm[1]; vtx3[2] = btm[2];
vtx2[0] = mid[0]; vtx2[1] = mid[1]; vtx2[2] = mid[2];
}
else
{
vtx2[0] = btm[0]; vtx2[1] = btm[1]; vtx2[2] = btm[2];
vtx3[0] = mid[0]; vtx3[1] = mid[1]; vtx3[2] = mid[2];
}
vtx1[0] = top[0]; vtx1[1] = top[1]; vtx1[2] = top[2];
}
else
{
float deltax = top[0] - btm[0];
float deltay = top[1] - btm[1];
float slope = deltax / deltay;
float x = mid[1] * slope - top[1] * slope + top[0];
vtx1[0] = top[0]; vtx1[1] = top[1]; vtx1[2] = top[2];
if (x < mid[0])
{
vtx2[0] = mid[0]; vtx2[1] = mid[1]; vtx2[2] = mid[2];
vtx3[0] = btm[0]; vtx3[1] = btm[1]; vtx3[2] = btm[2];
}
else
{
vtx2[0] = btm[0]; vtx2[1] = btm[1]; vtx2[2] = btm[2];
vtx3[0] = mid[0]; vtx3[1] = mid[1]; vtx3[2] = mid[2];
}
}
for (int i = (int)minx; i < (int)maxx; i++)
{
for (int j = (int)miny; j < (int)maxy; j++)
{
GzCoord point;
point[0] = i;
point[1] = j;
point[2] = 0;
if (LEE(vtx1, vtx2, point) >= 0 && LEE(vtx2, vtx3, point) >= 0 && LEE(vtx3, vtx1, point) >= 0)
{
/* Interpolate Z */
float vector1[3], vector2[3];
float *result = (float*)malloc(sizeof(float)* 3);
vector1[0] = vtx1[0] - vtx2[0]; vector1[1] = vtx1[1] - vtx2[1]; vector1[2] = vtx1[2] - vtx2[2];
vector2[0] = vtx3[0] - vtx2[0]; vector2[1] = vtx3[1] - vtx2[1]; vector2[2] = vtx3[2] - vtx2[2];
result = crossProduct(vector1, vector2);
if (result[0] * vtx2[0] + result[1] * vtx2[1] + result[2] * vtx2[2] == result[0] * vtx3[0] + result[1] * vtx3[1] + result[2] * vtx3[2])
int a = 3;
point[2] = (result[0] * vtx1[0] + result[1] * vtx1[1] + result[2] * vtx1[2] - result[0] * i - result[1] * j) / result[2];
///* Do the transformation */
//transform(render, point);
Rasterize(render->display, point[0], point[1],
ctoi(render->flatcolor[0]),
ctoi(render->flatcolor[1]),
ctoi(render->flatcolor[2]),
1, point[2]);
}
}
}
}
