Implement mesh creation in python.

[panzergame]

API example:

builder = KX_MeshBuilder(name, scene, [uvsName, colorsName])
builder = KX_MeshBuilder(name, scene, mesh)
     
mat = builder.addMaterial(material, primitiveType)
mat = builder.materials[i]
     
mat.addVertex(pos[, normal, tangent, uvs, colors]) -> index
mat.addIndex([i]) #for rendered primitive and physics in case of triangle primitive
mat.addPrimitiveIndex([i]) # only for rendered primitive
mat.addTriangleIndex([i]) # only for physics shape
     
mat.removeVertex(start[, end])
mat.removePrimitiveIndex(start[, end])
mat.removeTriangleIndex(start[, end])
     
mat.vertices -> [KX_VertexProxy]
mat.primitiveIndices -> [int]
mat.triangleIndices -> [int]
mat.material = mat

Example file: meshbuilder.zip

[BluePrintRandom]

I have used this api quite a bit

I think it's ready to merge, @lordloki @panzergame

later we may want to think about a 'merge' meshes command that absorbs a mesh from another object and removes that object (allowing it's transform to be manipulated) - example - adding planes(2 triangles) and triangles to build mesh in game and then absorbing all the pieces after it's transforms are correct viusally.

[BluePrintRandom]

#demo script and example of recalc normals in game 
import bge
from bge import *
import math
from mathutils import *

def recalcNormals( target ):
    #recalc normal command (also makes object mesh unique/ replica)

    if 'Copy' not in target:
        target.replaceMesh(target.meshes[0].copy(), 1, 1)
        target['Copy']=True
    builder = bge.types.KX_MeshBuilder.FromMesh("my mesh", target.meshes[0])
    builder.slots[0].recalculateNormals()
    mesh = builder.finish()
    oldMesh = target.meshes[0]
    target.replaceMesh(mesh,1,1)
    oldMesh.destruct()
    
def main():
    #demo moving vertex and recalculate normal 
    scene = logic.getCurrentScene()
    obj = logic.getCurrentController().owner
    own = logic.getCurrentController().owner
    origmesh = obj.meshes[0]

   
    for vert_index in range(own.meshes[0].getVertexArrayLength(0)):
        vert = own.meshes[0].getVertex(0,vert_index)
        snag = vert.XYZ 
        snag[2] += math.cos(snag[0]+1+(own['Timer']*12) )*.0125
        snag[1] += math.cos(snag[0]+1+(own['Timer']*12) ) *.0125
        vert.XYZ = snag
        #print('moved')
    recalcNormals(own)
    
main()