TerrainPatchData::TerrainPatchData(TerrainQuadtree* tree) :
tree(tree),
tessellation(tree->getPlanetarySurface()->getTessellation()),
vertices(tessellation + 3, std::vector<Ogre::Vector3>(tessellation + 3)),
normals(tessellation + 3, std::vector<Ogre::Vector3>(tessellation + 3)),
heights(tessellation + 3, std::vector<Ogre::Real>(tessellation + 3, 0.0)) {
int patchSize = tree->getSize();
Ogre::Real halfPatchSize = Ogre::Real(patchSize / 2);
Ogre::Real delta = (Ogre::Real)patchSize * (1.0 / (Ogre::Real)tessellation);
Ogre::SceneNode* patchSceneNode = tree->getSceneNode();
Ogre::SceneNode* planetarySceneNode = tree->getPlanetarySurface()->getSceneNode();
Ogre::Real planetaryRadius = (Ogre::Real)tree->getPlanetarySurface()->getRadius();
for (int z = -1; z < tessellation + 2; ++z) {
for (int x = -1; x < tessellation + 2; ++x) {
Ogre::Vector3 position(-halfPatchSize + delta * x, 0.0, -halfPatchSize + delta * z);
Ogre::Vector3 planetaryPosition = planetarySceneNode->convertWorldToLocalPosition(patchSceneNode->convertLocalToWorldPosition(position));
planetaryPosition = mapToSphere(planetaryPosition, planetaryRadius);
Ogre::Vector3 normal = planetaryPosition.normalisedCopy();
Ogre::Real height = tree->getPlanetarySurface()->getNoiseFunction()->getValue(planetaryPosition);
planetaryPosition = planetarySceneNode->convertLocalToWorldPosition(planetaryPosition);
position = patchSceneNode->convertWorldToLocalPosition(planetaryPosition);
normal = (tree->getRootSceneNode()->getOrientation().Inverse() * normal).normalisedCopy();
vertices[z + 1][x + 1] = position;
normals[z + 1][x + 1] = normal;
heights[z + 1][x + 1] = height;
}
}
for (int z = 0; z < tessellation + 1; ++z) {
for (int x = 0; x < tessellation + 1; ++x) {
processedPositions.push_back(getVertex(x, z));
processedNormals.push_back(getVertexNormal(x, z));
processedTextureCoords.push_back(getNormal(x, z));
}
}
// Add triangles.
for (int z = 0; z < tessellation; ++z) {
int zOffset = z * (tessellation + 1);
for (int x = 0; x < tessellation; ++x) {
int indices[4] = {
zOffset + x,
zOffset + x + 1,
zOffset + tessellation + 1 + x,
zOffset + tessellation + 1 + x + 1
};
processedIndices.push_back(indices[0]);
processedIndices.push_back(indices[2]);
processedIndices.push_back(indices[1]);
processedIndices.push_back(indices[2]);
processedIndices.push_back(indices[3]);
processedIndices.push_back(indices[1]);
}
}
}
