Transparent textures from images
- To: mathgroup at smc.vnet.net
- Subject: [mg123362] Transparent textures from images
- From: Patrick Scheibe <pscheibe at trm.uni-leipzig.de>
- Date: Sat, 3 Dec 2011 04:14:01 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
Hi, I sent this already to Wolfram, but maybe someone wants to try this on a windows machine. Starting from an image with alpha-channel data = Table[{Sin[x], Sin[y], 1, Sin[x y]}, {y, 0, 2 Pi, 2 Pi/127.}, {x, 0, 2 Pi, 2 Pi/127.}]; img = Image[data, ColorSpace -> "RGB"] AlphaChannel[img] When I use this now as texture on a cube, I expect the walls to be transparent according to the alpha-channel vtc = {{0, 0}, {1, 0}, {1, 1}, {0, 1}}; coords = {{{0, 0, 0}, {0, 1, 0}, {1, 1, 0}, {1, 0, 0}}, {{0, 0, 0}, {1, 0, 0}, {1, 0, 1}, {0, 0, 1}}, {{1, 0, 0}, {1, 1, 0}, {1, 1, 1}, {1, 0, 1}}, {{1, 1, 0}, {0, 1, 0}, {0, 1, 1}, {1, 1, 1}}, {{0, 1, 0}, {0, 0, 0}, {0, 0, 1}, {0, 1, 1}}, {{0, 0, 1}, {1, 0, 1}, {1, 1, 1}, {0, 1, 1}}}; Graphics3D[{Texture[img], Polygon[coords, VertexTextureCoordinates -> Table[vtc, {6}]]}, Boxed -> False] This does not work here. I get a cube with a white painting where it should be transparent. Using the pure {r,g,b,a} data I get the right result: Graphics3D[{Texture[data], Polygon[coords, VertexTextureCoordinates -> Table[vtc, {6}]]}, Boxed -> False] Can someone check this or give me a hint which part I understood wrong? Cheers Patrick