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project1D.cxx
544 lines (498 loc) · 21 KB
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project1D.cxx
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#include <iostream>
#include <vtkDataSet.h>
#include <vtkImageData.h>
#include <vtkPNGWriter.h>
#include <vtkPointData.h>
#include <vtkPolyData.h>
#include <vtkPolyDataReader.h>
#include <vtkPoints.h>
#include <vtkUnsignedCharArray.h>
#include <vtkFloatArray.h>
#include <vtkCellArray.h>
#include <algorithm>
#include <stdio.h>
using std::cerr;
using std::endl;
double max(double x, double y)
{
return (x > y) ? x : y;
}
double min(double x, double y)
{
return (x < y) ? x : y;
}
double ceil_441(double f)
{
return ceil(f-0.00001);
}
double floor_441(double f)
{
return floor(f+0.00001);
}
vtkImageData *
NewImage(int width, int height)
{
vtkImageData *img = vtkImageData::New();
img->SetDimensions(width, height, 1);
img->AllocateScalars(VTK_UNSIGNED_CHAR, 3);
return img;
}
void
WriteImage(vtkImageData *img, const char *filename)
{
std::string full_filename = filename;
full_filename += ".png";
vtkPNGWriter *writer = vtkPNGWriter::New();
writer->SetInputData(img);
writer->SetFileName(full_filename.c_str());
writer->Write();
writer->Delete();
}
class Triangle
{
public:
double X[3];
double Y[3];
double Z[3];
double color[3][3];
// would some methods for transforming the triangle in place be helpful?
};
class Screen
{
public:
unsigned char *buffer;
int width, height;
// would some methods for accessing and setting pixels be helpful?
};
std::vector<Triangle>
GetTriangles(void)
{
vtkPolyDataReader *rdr = vtkPolyDataReader::New();
rdr->SetFileName("proj1d_geometry.vtk");
cerr << "Reading" << endl;
rdr->Update();
cerr << "Done reading" << endl;
if (rdr->GetOutput()->GetNumberOfCells() == 0)
{
cerr << "Unable to open file!!" << endl;
exit(EXIT_FAILURE);
}
vtkPolyData *pd = rdr->GetOutput();
int numTris = pd->GetNumberOfCells();
vtkPoints *pts = pd->GetPoints();
vtkCellArray *cells = pd->GetPolys();
vtkFloatArray *var = (vtkFloatArray *) pd->GetPointData()->GetArray("hardyglobal");
float *color_ptr = var->GetPointer(0);
std::vector<Triangle> tris(numTris);
vtkIdType npts;
vtkIdType *ptIds;
int idx;
for (idx = 0, cells->InitTraversal() ; cells->GetNextCell(npts, ptIds) ; idx++)
{
if (npts != 3)
{
cerr << "Non-triangles!! ???" << endl;
exit(EXIT_FAILURE);
}
tris[idx].X[0] = pts->GetPoint(ptIds[0])[0];
tris[idx].X[1] = pts->GetPoint(ptIds[1])[0];
tris[idx].X[2] = pts->GetPoint(ptIds[2])[0];
tris[idx].Y[0] = pts->GetPoint(ptIds[0])[1];
tris[idx].Y[1] = pts->GetPoint(ptIds[1])[1];
tris[idx].Y[2] = pts->GetPoint(ptIds[2])[1];
tris[idx].Z[0] = pts->GetPoint(ptIds[0])[2];
tris[idx].Z[1] = pts->GetPoint(ptIds[1])[2];
tris[idx].Z[2] = pts->GetPoint(ptIds[2])[2];
// 1->2 interpolate between light blue, dark blue
// 2->2.5 interpolate between dark blue, cyan
// 2.5->3 interpolate between cyan, green
// 3->3.5 interpolate between green, yellow
// 3.5->4 interpolate between yellow, orange
// 4->5 interpolate between orange, brick
// 5->6 interpolate between brick, salmon
double mins[7] = { 1, 2, 2.5, 3, 3.5, 4, 5 };
double maxs[7] = { 2, 2.5, 3, 3.5, 4, 5, 6 };
unsigned char RGB[8][3] = { { 71, 71, 219 },
{ 0, 0, 91 },
{ 0, 255, 255 },
{ 0, 128, 0 },
{ 255, 255, 0 },
{ 255, 96, 0 },
{ 107, 0, 0 },
{ 224, 76, 76 }
};
for (int j = 0 ; j < 3 ; j++)
{
float val = color_ptr[ptIds[j]];
int r;
for (r = 0 ; r < 7 ; r++)
{
if (mins[r] <= val && val < maxs[r])
break;
}
if (r == 7)
{
cerr << "Could not interpolate color for " << val << endl;
exit(EXIT_FAILURE);
}
double proportion = (val-mins[r]) / (maxs[r]-mins[r]);
tris[idx].color[j][0] = (RGB[r][0]+proportion*(RGB[r+1][0]-RGB[r][0]))/255.0;
tris[idx].color[j][1] = (RGB[r][1]+proportion*(RGB[r+1][1]-RGB[r][1]))/255.0;
tris[idx].color[j][2] = (RGB[r][2]+proportion*(RGB[r+1][2]-RGB[r][2]))/255.0;
}
}
return tris;
}
void placeDownwardTrianglePixels(Triangle triangle, unsigned char *buffer, double* zvalues, int width, int height){
//find which vertices are which
double baseY1, baseX1, baseZ1, baseZ2, baseY2, baseX2, tipY, tipX, tipZ;
double baseRed1, baseGreen1, baseBlue1, baseRed2, baseGreen2, baseBlue2, tipRed, tipGreen, tipBlue;
if(triangle.Y[0] == triangle.Y[1]){
baseY1 = triangle.Y[0];
baseX1 = triangle.X[0] < triangle.X[1] ? triangle.X[0] : triangle.X[1];
baseY2 = triangle.Y[0];
baseX2 = triangle.X[0] < triangle.X[1] ? triangle.X[1] : triangle.X[0];
baseZ1 = triangle.X[0] < triangle.X[1] ? triangle.Z[0]:triangle.Z[1];
baseZ2 = triangle.X[0] < triangle.X[1] ? triangle.Z[1]:triangle.Z[0];
tipY = triangle.Y[2];
tipX = triangle.X[2];
tipZ = triangle.Z[2];
baseRed1 = triangle.X[0] < triangle.X[1] ? triangle.color[0][0] : triangle.color[1][0];
baseGreen1 = triangle.X[0] < triangle.X[1] ? triangle.color[0][1] : triangle.color[1][1];
baseBlue1 = triangle.X[0] < triangle.X[1] ? triangle.color[0][2] : triangle.color[1][2];
baseRed2 = triangle.X[0] < triangle.X[1] ? triangle.color[1][0] : triangle.color[0][0];
baseGreen2 = triangle.X[0] < triangle.X[1] ? triangle.color[1][1] : triangle.color[0][1];
baseBlue2 = triangle.X[0] < triangle.X[1] ? triangle.color[1][2] : triangle.color[0][2];
tipRed = triangle.color[2][0];
tipGreen = triangle.color[2][1];
tipBlue = triangle.color[2][2];
}else if(triangle.Y[0] == triangle.Y[2]){
baseY1 = triangle.Y[0];
baseX1 = triangle.X[0] < triangle.X[2] ? triangle.X[0] : triangle.X[2];
baseY2 = triangle.Y[0];
baseX2 = triangle.X[0] < triangle.X[2] ? triangle.X[2] : triangle.X[0];
baseZ1 = triangle.X[0] < triangle.X[2] ? triangle.Z[0]:triangle.Z[2];
baseZ2 = triangle.X[0] < triangle.X[2] ? triangle.Z[2]:triangle.Z[0];
tipY = triangle.Y[1];
tipX = triangle.X[1];
tipZ = triangle.Z[1];
baseRed1 = triangle.X[0] < triangle.X[2] ? triangle.color[0][0] : triangle.color[2][0];
baseGreen1 = triangle.X[0] < triangle.X[2] ? triangle.color[0][1] : triangle.color[2][1];
baseBlue1 = triangle.X[0] < triangle.X[2] ? triangle.color[0][2] : triangle.color[2][2];
baseRed2 = triangle.X[0] < triangle.X[2] ? triangle.color[2][0] : triangle.color[0][0];
baseGreen2 = triangle.X[0] < triangle.X[2] ? triangle.color[2][1] : triangle.color[0][1];
baseBlue2 = triangle.X[0] < triangle.X[2] ? triangle.color[2][2] : triangle.color[0][2];
tipRed = triangle.color[1][0];
tipGreen = triangle.color[1][1];
tipBlue = triangle.color[1][2];
}else{
baseY1 = triangle.Y[1];
baseX1 = triangle.X[1] < triangle.X[2] ? triangle.X[1] : triangle.X[2];
baseY2 = triangle.Y[1];
baseX2 = triangle.X[1] < triangle.X[2] ? triangle.X[2] : triangle.X[1];
baseZ1 = triangle.X[1] < triangle.X[2] ? triangle.Z[1]:triangle.Z[2];
baseZ2 = triangle.X[1] < triangle.X[2] ? triangle.Z[2]:triangle.Z[1];
tipY = triangle.Y[0];
tipX = triangle.X[0];
tipZ = triangle.Z[0];
baseRed1 = triangle.X[1] < triangle.X[2] ? triangle.color[1][0] : triangle.color[2][0];
baseGreen1 = triangle.X[1] < triangle.X[2] ? triangle.color[1][1] : triangle.color[2][1];
baseBlue1 = triangle.X[1] < triangle.X[2] ? triangle.color[1][2] : triangle.color[2][2];
baseRed2 = triangle.X[1] < triangle.X[2] ? triangle.color[2][0] : triangle.color[1][0];
baseGreen2 = triangle.X[1] < triangle.X[2] ? triangle.color[2][1] : triangle.color[1][1];
baseBlue2 = triangle.X[1] < triangle.X[2] ? triangle.color[2][2] : triangle.color[1][2];
tipRed = triangle.color[0][0];
tipGreen = triangle.color[0][1];
tipBlue = triangle.color[0][2];
}
//check if vertices are out of bounds
int minY, maxY;
minY = tipY >= 0 ? ceil_441(tipY) : 0;
maxY = baseY1 < height ? floor_441(baseY1) : height-1;
//find edge slopes
double slope1, slope2;
if(baseX1 != tipX){
slope1 = (tipY - baseY1)/(tipX - baseX1);
}else{
slope1 = 0;
}
if(baseX2 != tipX){
slope2 = (baseY2 - tipY)/(baseX2 - tipX);
}else{
slope2 = 0;
}
double red1, green1, blue1, red2, green2, blue2;
//scanline algorithm
for(int i = minY; i <= maxY; i++){
double pixelZ1, pixelZ2, pixelX1, pixelX2;
pixelZ1 = tipZ != baseZ1 ? baseZ1 + ((tipZ - baseZ1)/(tipY - baseY1))*(i - baseY2) : baseZ1;
pixelZ2 = tipZ != baseZ2 ? baseZ2 + ((tipZ - baseZ2)/(tipY - baseY2))*(i - baseY2) : baseZ2;
red1 = tipRed != baseRed1 ? baseRed1 + ((tipRed - baseRed1)/(tipY - baseY1))*(i - baseY2) : baseRed1;
red2 = tipRed != baseRed2 ? baseRed2 + ((tipRed - baseRed2)/(tipY - baseY2))*(i - baseY2) : baseRed2;
green1 = tipGreen != baseGreen1 ? baseGreen1 + ((tipGreen - baseGreen1)/(tipY - baseY1))*(i - baseY2) : baseGreen1;
green2 = tipGreen != baseGreen2 ? baseGreen2 + ((tipGreen - baseGreen2)/(tipY - baseY2))*(i - baseY2) : baseGreen2;
blue1 = tipBlue != baseBlue1 ? baseBlue1 + ((tipBlue - baseBlue1)/(tipY - baseY1))*(i - baseY2) : baseBlue1;
blue2 = tipBlue != baseBlue2 ? baseBlue2 + ((tipBlue - baseBlue2)/(tipY - baseY2))*(i - baseY2) : baseBlue2;
if(slope1 != 0){
pixelX1 = tipX + (i - tipY)/slope1;
}else{
pixelX1 = baseX1;
}
if(slope2 != 0){
pixelX2 = tipX + ((i) - tipY)/slope2;
}else{
pixelX2 = baseX2;
}
//check endpoint for out of bounds
int edgeX1, edgeX2;
edgeX1 = pixelX1 >= 0 ? ceil_441(pixelX1) : 0;
edgeX2 = pixelX2 < width ? floor_441(pixelX2) : width-1;
double pixelZ;
//place colors along line
for(int j = edgeX1; j <= edgeX2; j++){
pixelZ = (j - pixelX1) * ((pixelZ2 - pixelZ1)/(pixelX2 - pixelX1)) + pixelZ1;
int imageOffset = 3*(i * width + j);
if((pixelZ <= 0.0) && (pixelZ >= -1.0) && (pixelZ >= zvalues[i * width + j])){
zvalues[i * width + j] = pixelZ;
buffer[imageOffset] = ceil_441(255*((j - pixelX1)*((red2 - red1)/(pixelX2 - pixelX1)) + red1));
buffer[imageOffset + 1] = ceil_441(255*((j - pixelX1)*((green2 - green1)/(pixelX2 - pixelX1)) + green1));
buffer[imageOffset + 2] = ceil_441(255*((j - pixelX1)*((blue2 - blue1)/(pixelX2 - pixelX1)) + blue1));
}
}
}
}
void placeUpwardTrianglePixels(Triangle triangle, unsigned char *buffer, double* zvalues, int width, int height){
double baseY1, baseX1, baseZ1, baseZ2, baseY2, baseX2, tipY, tipX, tipZ;
double baseRed1, baseGreen1, baseBlue1, baseRed2, baseGreen2, baseBlue2, tipRed, tipGreen, tipBlue;
if(triangle.Y[0] == triangle.Y[1]){
baseY1 = triangle.Y[0];
baseX1 = triangle.X[0] < triangle.X[1] ? triangle.X[0] : triangle.X[1];
baseY2 = triangle.Y[0];
baseX2 = triangle.X[0] < triangle.X[1] ? triangle.X[1] : triangle.X[0];
baseZ1 = triangle.X[0] < triangle.X[1] ? triangle.Z[0]:triangle.Z[1];
baseZ2 = triangle.X[0] < triangle.X[1] ? triangle.Z[1]:triangle.Z[0];
tipY = triangle.Y[2];
tipX = triangle.X[2];
tipZ = triangle.Z[2];
baseRed1 = triangle.X[0] < triangle.X[1] ? triangle.color[0][0] : triangle.color[1][0];
baseGreen1 = triangle.X[0] < triangle.X[1] ? triangle.color[0][1] : triangle.color[1][1];
baseBlue1 = triangle.X[0] < triangle.X[1] ? triangle.color[0][2] : triangle.color[1][2];
baseRed2 = triangle.X[0] < triangle.X[1] ? triangle.color[1][0] : triangle.color[0][0];
baseGreen2 = triangle.X[0] < triangle.X[1] ? triangle.color[1][1] : triangle.color[0][1];
baseBlue2 = triangle.X[0] < triangle.X[1] ? triangle.color[1][2] : triangle.color[0][2];
tipRed = triangle.color[2][0];
tipGreen = triangle.color[2][1];
tipBlue = triangle.color[2][2];
}else if(triangle.Y[0] == triangle.Y[2]){
baseY1 = triangle.Y[0];
baseX1 = triangle.X[0] < triangle.X[2] ? triangle.X[0] : triangle.X[2];
baseY2 = triangle.Y[0];
baseX2 = triangle.X[0] < triangle.X[2] ? triangle.X[2] : triangle.X[0];
baseZ1 = triangle.X[0] < triangle.X[2] ? triangle.Z[0]:triangle.Z[2];
baseZ2 = triangle.X[0] < triangle.X[2] ? triangle.Z[2]:triangle.Z[0];
tipY = triangle.Y[1];
tipX = triangle.X[1];
tipZ = triangle.Z[1];
baseRed1 = triangle.X[0] < triangle.X[2] ? triangle.color[0][0] : triangle.color[2][0];
baseGreen1 = triangle.X[0] < triangle.X[2] ? triangle.color[0][1] : triangle.color[2][1];
baseBlue1 = triangle.X[0] < triangle.X[2] ? triangle.color[0][2] : triangle.color[2][2];
baseRed2 = triangle.X[0] < triangle.X[2] ? triangle.color[2][0] : triangle.color[0][0];
baseGreen2 = triangle.X[0] < triangle.X[2] ? triangle.color[2][1] : triangle.color[0][1];
baseBlue2 = triangle.X[0] < triangle.X[2] ? triangle.color[2][2] : triangle.color[0][2];
tipRed = triangle.color[1][0];
tipGreen = triangle.color[1][1];
tipBlue = triangle.color[1][2];
}else{
baseY1 = triangle.Y[1];
baseX1 = triangle.X[1] < triangle.X[2] ? triangle.X[1] : triangle.X[2];
baseY2 = triangle.Y[1];
baseX2 = triangle.X[1] < triangle.X[2] ? triangle.X[2] : triangle.X[1];
baseZ1 = triangle.X[1] < triangle.X[2] ? triangle.Z[1]:triangle.Z[2];
baseZ2 = triangle.X[1] < triangle.X[2] ? triangle.Z[2]:triangle.Z[1];
tipY = triangle.Y[0];
tipX = triangle.X[0];
tipZ = triangle.Z[0];
baseRed1 = triangle.X[1] < triangle.X[2] ? triangle.color[1][0] : triangle.color[2][0];
baseGreen1 = triangle.X[1] < triangle.X[2] ? triangle.color[1][1] : triangle.color[2][1];
baseBlue1 = triangle.X[1] < triangle.X[2] ? triangle.color[1][2] : triangle.color[2][2];
baseRed2 = triangle.X[1] < triangle.X[2] ? triangle.color[2][0] : triangle.color[1][0];
baseGreen2 = triangle.X[1] < triangle.X[2] ? triangle.color[2][1] : triangle.color[1][1];
baseBlue2 = triangle.X[1] < triangle.X[2] ? triangle.color[2][2] : triangle.color[1][2];
tipRed = triangle.color[0][0];
tipGreen = triangle.color[0][1];
tipBlue = triangle.color[0][2];
}
//check if vertices are out of bounds
int minY, maxY;
minY = baseY1 >= 0 ? ceil_441(baseY1) : 0;
maxY = tipY < height ? floor_441(tipY) : height-1;
//find edge slopes
double slope1, slope2;
if(baseX1 != tipX){
slope1 = (tipY - baseY1)/(tipX - baseX1);
}else{
slope1 = 0;
}
if(baseX2 != tipX){
slope2 = (baseY2 - tipY)/(baseX2 - tipX);
}else{
slope2 = 0;
}
double red1, green1, blue1, red2, green2, blue2;
//scanline algorithm
for(int i = minY; i <= maxY; i++){
double pixelZ1, pixelZ2, pixelX1, pixelX2;
pixelZ1 = tipZ != baseZ1 ? baseZ1 + ((tipZ - baseZ1)/(tipY - baseY1))*(i - baseY2) : baseZ1;
pixelZ2 = tipZ != baseZ2 ? baseZ2 + ((tipZ - baseZ2)/(tipY - baseY2))*(i - baseY2) : baseZ2;
red1 = tipRed != baseRed1 ? baseRed1 + ((tipRed - baseRed1)/(tipY - baseY1))*(i - baseY2) : baseRed1;
red2 = tipRed != baseRed2 ? baseRed2 + ((tipRed - baseRed2)/(tipY - baseY2))*(i - baseY2) : baseRed2;
green1 = tipGreen != baseGreen1 ? baseGreen1 + ((tipGreen - baseGreen1)/(tipY - baseY1))*(i - baseY2) : baseGreen1;
green2 = tipGreen != baseGreen2 ? baseGreen2 + ((tipGreen - baseGreen2)/(tipY - baseY2))*(i - baseY2) : baseGreen2;
blue1 = tipBlue != baseBlue1 ? baseBlue1 + ((tipBlue - baseBlue1)/(tipY - baseY1))*(i - baseY2) : baseBlue1;
blue2 = tipBlue != baseBlue2 ? baseBlue2 + ((tipBlue - baseBlue2)/(tipY - baseY2))*(i - baseY2) : baseBlue2;
//find lines endpoints
if(slope1 != 0){
pixelX1 = baseX1 + (i - baseY1)/slope1;
}else{
pixelX1 = (baseX1);
}
if(slope2 != 0){
pixelX2 = baseX2 + ((i) - baseY2)/slope2;
}else{
pixelX2 = (baseX2);
}
//check endpoint for out of bounds
int edgeX1, edgeX2;
edgeX1 = pixelX1 >= 0 ? ceil_441(pixelX1) : 0;
edgeX2 = pixelX2 < width ? floor_441(pixelX2) : width-1;
double pixelZ;
//place colors along line
for(int j = edgeX1; j <= edgeX2; j++){
pixelZ = (j - pixelX1) * ((pixelZ2 - pixelZ1)/(pixelX2 - pixelX1)) + pixelZ1;
int imageOffset = 3*(i * width + j);
if((pixelZ <= 0.0) && (pixelZ >= -1.0) && (pixelZ >= zvalues[i * width + j])){
zvalues[i * width + j] = pixelZ;
buffer[imageOffset] = ceil_441(255*((j - pixelX1)*((red2 - red1)/(pixelX2 - pixelX1)) + red1));
buffer[imageOffset + 1] = ceil_441(255*((j - pixelX1)*((green2 - green1)/(pixelX2 - pixelX1)) + green1));
buffer[imageOffset + 2] = ceil_441(255*((j - pixelX1)*((blue2 - blue1)/(pixelX2 - pixelX1)) + blue1));
}
}
}
}
void placeTrianglePixels(Triangle triangle, unsigned char *buffer, double* zvalues, int width, int height){
//check if triangle is up down or both
if(triangle.Y[0] == triangle.Y[1]){
if(triangle.Y[0] > triangle.Y[2]){
placeDownwardTrianglePixels(triangle, buffer, zvalues, width, height);
}
else{
placeUpwardTrianglePixels(triangle, buffer, zvalues, width, height);
}
}
else if(triangle.Y[0] == triangle.Y[2]){
if(triangle.Y[0] > triangle.Y[1]){
placeDownwardTrianglePixels(triangle, buffer, zvalues, width, height);
}
else{
placeUpwardTrianglePixels(triangle, buffer, zvalues, width, height);
}
}
else if(triangle.Y[2] == triangle.Y[1]){
if(triangle.Y[0] < triangle.Y[1]){
placeDownwardTrianglePixels(triangle, buffer, zvalues, width, height);
}
else{
placeUpwardTrianglePixels(triangle, buffer, zvalues, width, height);
}
}
else{
double minY, minX, minZ,minR, minG, minB;
double maxY, maxX,maxZ, maxR, maxG,maxB;
double splitY, splitX, splitZ, splitR, splitG, splitB;
minY = maxY = splitY = triangle.Y[0];
minX = maxX = splitX = triangle.X[0];
minZ = maxZ = splitZ = triangle.Z[0];
maxR = minR = splitR = triangle.color[0][0];
minG = maxG = splitG = triangle.color[0][1];
minB = maxB = splitB = triangle.color[0][2];
for(int i = 1; i<=2; i++){
if(maxY < triangle.Y[i]){
maxY = triangle.Y[i];
maxX = triangle.X[i];
maxZ = triangle.Z[i];
maxR = triangle.color[i][0];
maxG = triangle.color[i][1];
maxB = triangle.color[i][2];
}
}
for(int i = 1; i<=2; i++){
if(minY > triangle.Y[i]){
minY = triangle.Y[i];
minX = triangle.X[i];
minZ = triangle.Z[i];
minR = triangle.color[i][0];
minG = triangle.color[i][1];
minB = triangle.color[i][2];
}
}
for(int i = 0; i<=2; i++){
if((maxY > triangle.Y[i]) && (minY < triangle.Y[i])){
splitY = triangle.Y[i];
splitX = triangle.X[i];
splitZ = triangle.Z[i];
splitR = triangle.color[i][0];
splitG = triangle.color[i][1];
splitB = triangle.color[i][2];
}
}
Triangle upwardTriangle,downwardTriangle;
upwardTriangle.Y[0] = maxY;
upwardTriangle.X[0] = maxX;
upwardTriangle.Z[0] = maxZ;
downwardTriangle.Y[0] = minY;
downwardTriangle.X[0] = minX;
downwardTriangle.Z[0] = minZ;
upwardTriangle.Y[1] = downwardTriangle.Y[1] = splitY;
upwardTriangle.X[1] = downwardTriangle.X[1] = splitX;
upwardTriangle.Z[1] = downwardTriangle.Z[1] = splitZ;
upwardTriangle.Y[2] = downwardTriangle.Y[2] = splitY;
upwardTriangle.X[2] = downwardTriangle.X[2] = minX + ((maxX - minX)/(maxY - minY))*(splitY - minY);
upwardTriangle.Z[2] = downwardTriangle.Z[2] = minZ + ((maxZ - minZ)/(maxY - minY))*(splitY - minY);
upwardTriangle.color[0][0] = maxR;
upwardTriangle.color[0][1] = maxG;
upwardTriangle.color[0][2] = maxB;
downwardTriangle.color[0][0] = minR;
downwardTriangle.color[0][1] = minG;
downwardTriangle.color[0][2] = minB;
upwardTriangle.color[1][0] = downwardTriangle.color[1][0] = splitR;
upwardTriangle.color[1][1] = downwardTriangle.color[1][1] = splitG;
upwardTriangle.color[1][2] = downwardTriangle.color[1][2] = splitB;
upwardTriangle.color[2][0] = downwardTriangle.color[2][0] = minR + ((maxR - minR)/(maxY - minY))*(splitY - minY);
upwardTriangle.color[2][1] = downwardTriangle.color[2][1] = minG + ((maxG - minG)/(maxY - minY))*(splitY - minY);
upwardTriangle.color[2][2] = downwardTriangle.color[2][2] = minB + ((maxB - minB)/(maxY - minY))*(splitY - minY);
placeDownwardTrianglePixels(downwardTriangle, buffer, zvalues, width, height);
placeUpwardTrianglePixels(upwardTriangle, buffer, zvalues, width, height);
}
}
int main()
{
int width = 1000, height = 1000;
vtkImageData *image = NewImage(width, height);
unsigned char *buffer =
(unsigned char *) image->GetScalarPointer(0,0,0);
int npixels = width*height;
double zvalues[npixels];
std::fill_n(zvalues, npixels, -1.0);
for (int i = 0 ; i < npixels*3 ; i++)
buffer[i] = 0;
std::vector<Triangle> triangles = GetTriangles();
Screen screen;
screen.buffer = buffer;
screen.width = width;
screen.height = height;
//places all traingles one by one
for(int j = 0; j < triangles.size(); j++){
placeTrianglePixels(triangles[j],buffer,zvalues,width,height);
}
WriteImage(image, "allTriangles");
}