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Working With Large Textures

As mentioned, tdlmake has tdlmake has been designed to adapt very well to huge work with any textures, including very large production-grade textures. One exception is compressed TIFFs that have a large "rows per strip" value. Here is an example output of tiffinfo on of tiffinfo on a large texture file that can cause problems for tdlmakefor tdlmake: 

% tiffinfo earth.tif
  Image Width: 43200 Image Length: 21600
  Resolution: 72, 72 (unitless)
  Bits/Sample: 8
  Compression Scheme: AdobeDeflate
  Photometric Interpretation: RGB color
  FillOrder: msb-to-lsb
  Software: "ImageMagick 5.5.7 07/22/03 Q16 http://www.imagemagick.org"
  Document Name: "earth.tif"
  Orientation: row 0 top, col 0 lhs
  Samples/Pixel: 3
  Rows/Strip: 21600
  Planar Configuration: single image plane
  Predictor: horizontal differencing 2 (0x2)

 There is only one strip, made of 21600 (total image height) rows. This means that accessing any scanline in this TIFF forces the TIFF reading library to uncompress the entire file(12). In order to lower memory usage for such large files, it is suggested that a lower "rows per strip" count be used. Typically, 16 or 32 scanlines is a good choice. tdlmake prints a warning if it encounters a file that has the aforementioned problem:

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Here are some examples using tdlmake on the command line:

To create a texture named `gridgrid.tdl' from a TIFF named `gridgrid.tif' using a gaussian downsampling filter of width 4:

tdlmake -filter gaussian -filterwidth 4 grid.tif grid.tdl

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To create a cubic environment map in which all cube sides were rendered using 90 degrees field of view:

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