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documentation:development:opera:pf25:ppgfldr:smmfldr:gspfldr:12pgs034

lrex

Demonstrates subcel extraction from an image.

Synopsis

lrex <imagefile>

Description

Demonstrates how to extract a cel from a frame buffer or bitmap image, that can then be redrawn into the frame buffer. Can be used for things like breaking up a static or dynamic image (like the video in Mystery Matinee in Twisted) and reorganizing it.

Subcel extraction from a frame buffer (bitmap) is slightly different from extraction from another cel. This program handles extraction from bitmaps only.

The extraction can easily be done with the appropriate call to the Lib3DO functions (CreateLRFormCel), but this example shows how to do it long hand.

When extracting from bitmaps, pay attention to the order in which the pixels are represented.

The program is based on animsample and aaplayer. The user can manipulate the extracted cel.

Caveats

In performing the cel manipulation, the source for the cel may end up pointing to garbage. This is especially likely if the program is distorting the cel near the edge of the extracting bitmap.

You can only extract a cel from even lines of the bitmap. This restriction arises out of the way bitmaps are laid out and lrfrom cels are drawn. You can extract from odd lines, but the cel will not be pixel accurate in relation to the source you are extracting from.

Arguments

  • imagefile Name of 3DO image file.

Associated Files

lrex.c, lrexerror.h, lrex.h

Location

examples/Graphics/lrex

documentation/development/opera/pf25/ppgfldr/smmfldr/gspfldr/12pgs034.txt · Last modified: 2022/10/10 16:53 by 127.0.0.1