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Vector Quantities

Visualize vector-valued data at the elements of a volume mesh.

volume mesh vector values

Example: showing vectors on vertices (here random vectors)

/* ... initialization, create mesh ... */ 

// Register the volume mesh with Polyscope
polyscope::registerTetMesh("my mesh", verts, tets);

// Add a vector quantity
size_t nVerts = V.rows();
std::vector<std::array<double, 3>> randVec(nVerts);
for (size_t i = 0; i < nVerts; i++) {
  // use random vectors as test data
  randVec[i] = {{polyscope::randomUnit() - .5, 
                 polyscope::randomUnit() - .5, 
                 polyscope::randomUnit() - .5}};
}
auto vectorQ = polyscope::getVolumeMesh("my mesh")->addVertexVectorQuantity("random vec", randVec);

// Set some options
vectorQ->setEnabled(true);           // initially enabled
vectorQ->setVectorLengthScale(0.05); // make the vectors bigger

// Show the GUI
polyscope::show();

Add vectors to elements

VolumeMesh::addVertexVectorQuantity(std::string name, const T& vectors, VectorType vectorType = VectorType::STANDARD)

Add a vector quantity defined at the vertices of the mesh.

  • vectors is the array of vectors at vertices. The type should be adaptable to a 3-vector array of floats. The length should be the number of vertices in the mesh.
  • vectorType indicates how to interpret vector data. The default setting is as a freely-scaled value, which will be automatically scaled to be visible. Passing VectorType::AMBIENT ensures vectors have the proper world-space length.

Note: the inner vector type of the input must be 3D dimensional, or you risk compiler errors, segfaults, or worse.

VolumeMesh::addCellVectorQuantity(std::string name, const T& vectors, VectorType vectorType = VectorType::STANDARD)

Add a vector quantity defined at the cells of the mesh.

  • vectors is the array of vectors at cells. The type should be adaptable to a 3-vector array of floats. The length should be the number of cells in the mesh.
  • vectorType indicates how to interpret vector data. The default setting is as a freely-scaled value, which will be automatically scaled to be visible. Passing VectorType::AMBIENT ensures vectors have the proper world-space length.

Note: the inner vector type of the input must be 3D dimensional, or you risk compiler errors, segfaults, or worse.

Options

Parameter Meaning Getter Setter Persistent?
enabled is the quantity enabled? bool isEnabled() setEnabled(bool newVal) yes
vector radius the radius vectors are drawn with double getVectorRadius() setVectorRadius(double val, bool isRelative=true) yes
vector length vectors will be scaled so the longest is this long. ignored if VectorType::Ambient double getVectorLengthScale() setVectorLengthScale(double val, bool isRelative=true) yes
vector color the color to draw the vectors with glm::vec3 getVectorColor() setVectorColor(glm::vec3 val) yes
material what material to use std::string getMaterial() setMaterial(std::string name) yes

(all setters return this to support chaining. setEnabled() returns generic quantity, so chain it last)