NAME

OpenGL::Image::Common - copyright 2007 Graphcomp - ALL RIGHTS RESERVED
Author: Bob "grafman" Free - grafman@graphcomp.com

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

DESCRIPTION

This module provides a base class for OpenGL imaging engines.
Requires the OpenGL module.

SYNOPSIS

##########
# Check for installed imaging engines

use OpenGL::Image::Common;
my $img = new OpenGL::Image::Common(%params);


##########
# Must supply width and height, or source:

# source - source image file path (some engines supports URLs).
# width,height - width and height in pixels for cache allocation.


##########
# Optional params:

# engine - specifies imaging engine; defaults to 'Targa'.


##########
# Methods defined in this Common module:

# Get native engine object
# Note: must not change image dimensions
my $obj = $img->Native;
$obj->Quantize() if ($obj);

# Alternately (Assuming the native engine supports Blur):
$img->Native->Blur();

# Test if image width is a power of 2
if ($img->IsPowerOf2());

# Test if all listed values are a power of 2
if ($img->IsPowerOf2(@list));

# Get largest power of 2 size within dimensions of image
my $size = $img->GetPowerOf2();

# Get all parameters as a hashref
my $params = $img->Get();

# Get one or more parameter values
my @values = $img->Get(@params);

# Get/Set Pixel values (normalized to 1.0)
my($r,$g,$b,$a) = $img->GetPixel($x,$y);

# Sync cache after done modifying pixels
$img->SetPixel($x,$y,$r,$g,$b,$a);
$frame->Sync();


##########
# Supported parameters:

# version - version of the engine
# source - source image, if defined
# width - width of image in pixels
# height - height of image in pixels
# pixels - number of pixels
# components - number of pixel components
# size - bytes per component
# length - cache size in bytes
# endian - 1 if big endian; otherwise 0
# alpha - 1 if has alpha channel, -1 if has inverted alpha channel; 0 if none
# flipped - 1 bit set if cache scanlines are top to bottom; others reserved
# gl_internalformat - internal GL pixel format. eg: GL_RGBA8, GL_RGBA16
# gl_format - GL pixel format. eg: GL_RGBA, GL_BGRA
# gl_type - GL data type.  eg: GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT


##########
# APIs defined in engine modules:

# Get engine version
my $ver = OpenGL::Image::ENGINE_MODULE::EngineVersion();

# Get engine description
my $desc = OpenGL::Image::ENGINE_MODULE::EngineDescription();


##########
# Methods defined in engine modules:

# Sync the image cache after modifying pixels.
# Used by some engines for paged caches; otherwise a NOP.
$img->Sync();

# Return the image's cache as an OpenGL::Array object.
# Note: OGA may change after a cache update
my $oga = $img->GetArray();

# Return a C pointer to the image's cache.
# For use with OpenGL's "_c" APIs.
# Note: pointer may change after a cache update
$img->Ptr();

# Save the image to a PNG file (assuming the native engine supports PNGs).
$img->Save('MyImage.png');

# Get image blob.
my $blob = $img->GetBlob();