Vector4d Triangle::normal_vector(const Vector4d &surface) const {
double u, v;
std::tie(u, v) = uvCoords(surface);
Vector4d normal = (1 - u - v) * n1 + u * n2 + v * n3;
normal.normalize();
return normal;
}
/*
This function is very slow.
Look into greedy meshing algorithms as an alternative
*/
void Chunk::GenrateCube(const glm::ivec3& pos, const glm::ivec3& worldPos)
{
visible_ = true;
char drawSides;
bool drawTop = true;
bool drawBottom = true;
bool drawLeft = true;
bool drawRight = true;
bool drawFront = true;
bool drawBack = true;
int x = pos.x;
int y = pos.y;
int z = pos.z;
//cube vertices.
glm::ivec3 v1p = v1p_ + pos;
glm::ivec3 v2p = v2p_ + pos;
glm::ivec3 v3p = v3p_ + pos;
glm::ivec3 v4p = v4p_ + pos;
glm::ivec3 v5p = v5p_ + pos;
glm::ivec3 v6p = v6p_ + pos;
glm::ivec3 v7p = v7p_ + pos;
glm::ivec3 v8p = v8p_ + pos;
glm::vec2 uvCoords(0,0);
int v1, v2, v3, v4, v5, v6, v7, v8; //vertex indexes
//below if block filters out any block sides which cant be visible. Reducing vertex count, and preventing graphical artifacts
if(y > 0)
drawTop = !blocks_[x][y-1][z].IsVisible();
if(y < chunkSize_-1)
drawBottom = !blocks_[x][y+1][z].IsVisible();
if(x > 0)
drawLeft = !blocks_[x-1][y][z].IsVisible();
if(x < chunkSize_-1)
drawRight = !blocks_[x+1][y][z].IsVisible();
if(z > 0)
drawBack = !blocks_[x][y][z-1].IsVisible();
if(z < chunkSize_-1)
drawFront = !blocks_[x][y][z+1].IsVisible();
////this if block checks the squares next to the outer edge blocks in the chunk to see if they are invisible. If they are
////visible, dont draw these edges.
if(y == 0)
drawTop = !GetBlockType(worldPos.x, worldPos.y - 1, worldPos.z );
if(y == CHUNK_SIZE-1)
drawBottom = !GetBlockType(worldPos.x, worldPos.y + 1, worldPos.z );
if(x == 0)
drawLeft = !GetBlockType(worldPos.x - 1, worldPos.y, worldPos.z );
if(x == CHUNK_SIZE-1)
drawRight = !GetBlockType(worldPos.x + 1, worldPos.y, worldPos.z );
if(z == 0)
drawBack = !GetBlockType(worldPos.x , worldPos.y, worldPos.z - 1);
if(z == CHUNK_SIZE-1)
drawFront = !GetBlockType(worldPos.x , worldPos.y, worldPos.z + 1);
////bottom
if(drawBottom)
{
//uvCoords = glm::vec2(1-uvStep_ + d_,0);
v5 = AddMeshVertex(v5p, downNormal_, uvCoords);
//uvCoords = glm::vec2(1 - d_,0);
v6 = AddMeshVertex(v6p, downNormal_, uvCoords);
//uvCoords = glm::vec2(1 ,uvStep_ - d_);
v7 = AddMeshVertex(v7p, downNormal_, uvCoords);
//uvCoords = glm::vec2(1-uvStep_ + d_,uvStep_ - d_);
v8 = AddMeshVertex(v8p, downNormal_, uvCoords);
//tessilate face
meshStorage_->GetData().AddTriangleToMesh(v8, v5, v7);
meshStorage_->GetData().AddTriangleToMesh(v8, v7, v6);
}
////top
if(drawTop)
{
//uvCoords = glm::vec2(0+d_,0+d_);
v1 = AddMeshVertex(v1p, upNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_ -d_,0+d_);
v2 = AddMeshVertex(v2p, upNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_ -d_,uvStep_-d_);
v3 = AddMeshVertex(v3p, upNormal_, uvCoords);
//uvCoords = glm::vec2(0+d_,uvStep_ - d_);
v4 = AddMeshVertex(v4p, upNormal_, uvCoords);
meshStorage_->GetData().AddTriangleToMesh(v2, v4, v1);
meshStorage_->GetData().AddTriangleToMesh(v3, v4, v2);
}
//left face
if(drawLeft)
{
//uvCoords = glm::vec2(uvStep_,0);
v1 = AddMeshVertex(v1p, leftNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2, 0);
v4 = AddMeshVertex(v4p, leftNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2,uvStep_);
v5 = AddMeshVertex(v5p, leftNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_,uvStep_);
v7 = AddMeshVertex(v7p, leftNormal_, uvCoords);
meshStorage_->GetData().AddTriangleToMesh(v4, v5, v1);
meshStorage_->GetData().AddTriangleToMesh(v4, v7, v5);
}
//right face
if(drawRight)
{
//uvCoords = glm::vec2(uvStep_,0);
v2 = AddMeshVertex(v2p, rightNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2, 0);
v3 = AddMeshVertex(v3p, rightNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2,uvStep_);
v6 = AddMeshVertex(v6p, rightNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_,uvStep_);
v8 = AddMeshVertex(v8p, rightNormal_, uvCoords);
meshStorage_->GetData().AddTriangleToMesh(v6, v3, v2);
meshStorage_->GetData().AddTriangleToMesh(v6, v2, v8);
}
//front face
if(drawFront)
{
//uvCoords = glm::vec2(uvStep_,0);
v7 = AddMeshVertex(v7p, frontNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2, 0);
v6 = AddMeshVertex(v6p, frontNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2,uvStep_);
v3 = AddMeshVertex(v3p, frontNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_,uvStep_);
v4 = AddMeshVertex(v4p, frontNormal_, uvCoords);
meshStorage_->GetData().AddTriangleToMesh(v7, v4, v3);
meshStorage_->GetData().AddTriangleToMesh(v7, v3, v6);
}
//back face
if(drawBack)
{
//uvCoords = glm::vec2(uvStep_,0);
v1 = AddMeshVertex(v1p, backNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2, 0);
v2 = AddMeshVertex(v2p, backNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_*2,uvStep_);
v5 = AddMeshVertex(v5p, backNormal_, uvCoords);
//uvCoords = glm::vec2(uvStep_,uvStep_);
v8 = AddMeshVertex(v8p, backNormal_, uvCoords);
meshStorage_->GetData().AddTriangleToMesh(v5, v2, v1);
meshStorage_->GetData().AddTriangleToMesh(v5, v8, v2);
}
}
