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TGLLines
Lines are basically points connected by lines. Points are called nodes here. Lines have
Width with same perspective restrictions like points. Nodes can be visible or not and can be
represented by cubes, stars or spheres with changeable size.
TGLPlane
Plane is a single quad. Quad is a polygon composed of four vertices and two triangles.
Plane has Width and Height values. Direction of the plane is important. It points in the direction of
normal of the plane. Normal is a vector that tells us which side if front and which side is back. If we
look at the plane from the front side we can see it, if we look from the back side we cant see it. You
will be able to see the plane only if its direction will point towards the camera.
Vertex shading can sometimes create problems with large planes. If edges of the plane are
stretched out too far from the reach of lights the plane will become dark as a whole.
TGLPolygon
[TODO]
TGLCube
Cube is composed of six planes, each plane can be disabled. Cube has CubeWidth,
CubeHeight and CubeDepth properties.
TGLFrustrum
Frustrum is a twisted cube with variable size of top and bottom sides.
TGLSphere
Radius is the size of the cube, Segments specifies how many polygons will be used to
draw the cube and how smooth the curvature will be.
TGLDisk
[TODO]
TGLCone
[TODO]
TGLCylinder
[TODO]
TGLDodecahedron
[TODO]
TGLIcosahedron
[TODO]
Advanced geometry
More complicated than basic geometry but the description is the same.
GLScene beginner's guide, Jan Zizka, 2005