void terrainComputeNormals() {
float *norm1,*norm2,*norm3,*norm4;
int i,j,k;
if (terrainNormals == NULL)
return;
for(i = 0; i < terrainGridLength; i++)
for(j = 0; j < terrainGridWidth; j++) {
norm1 = NULL;
norm2 = NULL;
norm3 = NULL;
norm4 = NULL;
/* normals for the four corners */
if (i == 0 && j == 0) {
norm1 = terrainCrossProduct(0,0, 0,1, 1,0);
terrainNormalize(norm1);
}
else if (j == terrainGridWidth-1 && i == terrainGridLength-1) {
norm1 = terrainCrossProduct(j,i, j,i-1, j-1,i);
terrainNormalize(norm1);
}
else if (j == 0 && i == terrainGridLength-1) {
norm1 = terrainCrossProduct(j,i, j+1,i, j,i-1);
terrainNormalize(norm1);
}
else if (j == terrainGridWidth-1 && i == 0) {
norm1 = terrainCrossProduct(j,i, j-1,i, j,i+1);
terrainNormalize(norm1);
}
/* normals for the borders */
else if (i == 0) {
norm1 = terrainCrossProduct(j,0, j-1,0, j,1);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,0,j,1,j+1,0);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
}
else if (j == 0) {
norm1 = terrainCrossProduct(0,i, 1,i, 0,i-1);
terrainNormalize(norm1);
norm2
= terrainCrossProduct(0,i, 0,i+1, 1,i);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
}
else if (i == terrainGridLength-1) {
norm1 = terrainCrossProduct(j,i, j+1,i, j,i-1);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,i, j,i-1, j-1,i);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
}
else if (j == terrainGridWidth-1) {
norm1 = terrainCrossProduct(j,i, j,i-1, j-1,i);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,i, j-1,i, j,i+1);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
}
/* normals for the inner vertices using 8 neighbours */
else {
norm1 = terrainCrossProduct(j,i, j-1,i, j-1,i+1);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,i, j-1,i+1, j,i+1);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
norm2 = terrainCrossProduct(j,i, j,i+1, j+1,i+1);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
norm2 = terrainCrossProduct(j,i, j+1,i+1, j+1,i);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
norm2 = terrainCrossProduct(j,i, j+1,i, j+1,i-1);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
norm2 = terrainCrossProduct(j,i, j+1,i-1, j,i-1);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
norm2 = terrainCrossProduct(j,i, j,i-1, j-1,i-1);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
norm2 = terrainCrossProduct(j,i, j-1,i-1, j-1,i);
terrainNormalize(norm2);
terrainAddVector(norm1,norm2);
free(norm2);
}
terrainNormalize(norm1);
norm1[2] = - norm1[2];
for (k = 0; k< 3; k++)
terrainNormals[3*(i*terrainGridWidth + j) + k] = norm1[k];
free(norm1);
}
}
void terrainComputeNormals() {
float *norm1,*norm2,*norm3,*norm4;
int i,j,k;
if (terrainNormals == NULL)
return;
for(i = 0; i < length; i++)
for(j = 0; j < width; j++)
{
norm1 = NULL;
norm2 = NULL;
norm3 = NULL;
norm4 = NULL;
// normals for the four corners
if (i == 0 && j == 0) {
norm1 = terrainCrossProduct(0,0, 0,1, 1,0);
terrainNormalize(norm1);
}
else if (j == width-1 && i == length-1) {
norm1 = terrainCrossProduct(i,j, j,i-1, j-1,i);
terrainNormalize(norm1);
}
else if (j == 0 && i == length-1) {
norm1 = terrainCrossProduct(i,j, j,i-1, j+1,i);
terrainNormalize(norm1);
}
else if (j == width-1 && i == 0) {
norm1 = terrainCrossProduct(i,j, j,i+1, j-1,i);
terrainNormalize(norm1);
}
// normals for the borders
else if (i == 0) {
norm1 = terrainCrossProduct(j,0, j-1,0, j,1);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,0,j,1,j+1,0);
terrainNormalize(norm2);
}
else if (j == 0) {
norm1 = terrainCrossProduct(0,i, 1,i, 0,i-1);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(0,i, 0,i+1, 1,i);
terrainNormalize(norm2);
}
else if (i == length-1) {
norm1 = terrainCrossProduct(j,i, j,i-1, j+1,i);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,i, j+1,i, j,i-1);
terrainNormalize(norm2);
}
else if (j == width-1) {
norm1 = terrainCrossProduct(j,i, j,i-1, j-1,i);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,i, j-1,i, j,i+1);
terrainNormalize(norm2);
}
// normals for the interior
else {
norm1 = terrainCrossProduct(j,i, j-1,i, j,i+1);
terrainNormalize(norm1);
norm2 = terrainCrossProduct(j,i, j,i+1, j+1,i);
terrainNormalize(norm2);
norm3 = terrainCrossProduct(j,i, j+1,i, j,i-1);
terrainNormalize(norm3);
norm4 = terrainCrossProduct(j,i, j,i-1, j-1,i);
terrainNormalize(norm4);
}
if (norm2 != NULL) {
terrainAddVector(norm1,norm2);
free(norm2);
}
if (norm3 != NULL) {
terrainAddVector(norm1,norm3);
free(norm3);
}
if (norm4 != NULL) {
terrainAddVector(norm1,norm4);
free(norm4);
}
terrainNormalize(norm1);
norm1[2] = - norm1[2];
for (k = 0; k< 3; k++)
{
terrainNormals[3*(i*width + j) + k] = norm1[k];
if((3*(i*width + j) + k) >= width *length*3)
{
std::cout<<"\nfunc:terrainComputeNormals() This can cause a heap corruption !!!";
std::cout<<"\nvalue is: "<<3*(i*width + j) + k;
}
}
free(norm1);
}
}
