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Grid3D and Octree

Brakeza3D includes Grid3D and Octree data structures integrated into Mesh3D objects.

  • Grid3D: Creates a grid of X, Y, Z dimensions over the AABB of the given object.
  • Octree: Creates an octree with the specified depth (maxDepth).

To create a grid in a Mesh3D object, use BuildGrid3D(sizeX, sizeY, sizeZ):

eye = ObjectFactory.Mesh3D(
    "../assets/models/Capsule.fbx",
    Vertex3D.new(x, y, z)
)
eye:BuildGrid3D(5, 5, 5)                                                    -- creates a 5x5x5 grid

To create an octree use BuildOctree(int maxDepth):

eye = ObjectFactory.Mesh3D("../assets/models/Capsule.fbx", Vertex3D.new(x, y, z))
eye:BuildOctree(1) -- crea una árbol de octanos de un solo nivel de profundidad, solo 8 hijos

To readjust the dimensions of both grids and octree structures, simply rerun buildGrid3D() or buildOctree().

Filling Geometry in Grid3D​

Grid3D stores a boolean flag for each cell. Brakeza3D provides a method fillGrid3DFromGeometry, which sets this flag for each cell if no triangle intersects or is contained in it:

eye = ObjectFactory.Mesh3D("../assets/models/Capsule.fbx", Vertex3D.new(x, y, z))
eye:BuildGrid3D(5, 5, 5)
eye:FillGrid3DFromGeometry()                -- sets flags for empty cells

This is especially useful for pathfinding techniques.

Pathfinding in Grid3D​

Grids include an A* algorithm that allows iterating over their cells. Combined with fillGrid3DFromGeometry, paths can avoid cells with geometry:

eye = ObjectFactory.Mesh3D("../assets/models/Capsule.fbx", Vertex3D.new(x, y, z))
eye:BuildGrid3D(5, 5, 5)
eye:FillGrid3DFromGeometry()                    -- fill with geometry

eye:getGrid3D():setTravel(0, 0, 0, 5, 5, 5)     -- set travel from (0,0,0) to (5,5,5)
path = eye:getGrid3D():MakeTravelCubesGrid()    -- returns an array of CubeGrid3D

Mediante el método setTravel(x1, y1, z1, x2, y2, z2), podremos ajustar el viaje para el próximo camino solicitado mediante makeTravelCubesGrid.

The method MakeTravelCubesGrid returns the requested path as an array of CubeGrid3D structures:

struct CubeGrid3D {
    AABB3D box;             // bounding box
    int posX;               // X index in the grid
    int posY;               // Y index
    int posZ;               // Z index
    bool passed = true;     // Flag
};

You can iterate over this array to obtain the desired path:

...
path = eye:getGrid3D():MakeTravelCubesGrid()            -- we get a travel path

for i, cube in ipairs(path) do
    print("Cube " .. i .. ": X = " .. cube.posX .. ", Y = " .. cube.posY .. ", Z = " .. cube.posZ)
end
...

Click object detection​

Brakeza3D ofrece de forma nativa la funcionalidad de click sobre un Object3D. Para ello po

Complete LUA Code Examples

https://github.com/rzeronte/brakeza3d/blob/master/doc/examples-lua-code.md_