Version 1 (modified by martin, 10 years ago)


Transparent Textures have a 4th component of colour (RGB image becomes RGBA) with the A component defining how transparent each pixel is. Typical uses:

  • a ragged tree line or a hedge - make a texture with transparency near the top and the polygons will look ragged.
  • clouds - cover the sky with a single rectangle, and apply a partly transparent texture to show clouds.

I have used the following techniques to create transparent textures.

i) PhotoShop? Elements - the cheap version of PhotoShop?.

Load a picture (scan, use digital camera, whatever) Use the Layers tab, double click the Background layer and make it a normal layer (just accept the default options that appear) Select an area of the image that you wish to be transparent, and use the menu option Edit->Clear. Save as a PNG format and apply to a polygon.

ii) Ulead PhotoImpact? (I acquired this program as a full free cover disc program, it is good value anyway)

Load the picture as Photoshop use the magic wand tool or other to select an area. (The wand allows irregular areas to be selected by colour) save the image as PNG format (by a miracle of PhotoImpact?, all selected areas are saved as opaque in PNG format).