Trouble with Perspective
- To: mathgroup at smc.vnet.net
- Subject: [mg124955] Trouble with Perspective
- From: Mark Green <p0073857 at brookes.ac.uk>
- Date: Tue, 14 Feb 2012 06:37:58 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
I'm trying this method based on the example from the Documentation
Centre to create a perspective projection:
teapot := Translate[ExampleData[{"Geometry3D", "UtahTeapot"},
"GraphicsComplex"], {-0.5, 0, -0.6}];
t := TransformationMatrix[RescalingTransform[{{-10, 10}, {-10, 10},
{-3/2, 5/2}}]];
Manipulate[
Graphics3D[Rotate[teapot, xs, {1, 0, 0}], Axes -> True,
ViewMatrix -> {t, {{1, 0, 0, -dx}, {0, 1, 0, -dy}, {0, 0, 1, 0},
{0, 0, -1/d, 0}}}, Lighting -> {{"Ambient", White}}],
{xs, 0, Pi}, {d, 0.1, -10}, {dx, -10, 10}, {dy, -10, 10}]
The problem is that the vanishing point of the perspective projection
is always way down in the corner of the image, and there doesn't seem
to be any way I can alter dx/dy or the RescalingTransform to get it
into the centre (which is where I want it). Is there a way to do
this?
Also, is there a way to have the axes in a 3D image displayed as lines
crossing at the origin point rather than along the edges of the image?