NAME
OpenGL::Image - 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 is an extensible wrapper to abstract imaging interfaces
By default, this module uses the Image::Magick module; support for
other imaging libraries may be added by providing plug-in modules
in the OpenGL/Image folder.
For the best performance, ImageMagick 6.3.5 or newer should be installed.
SYNOPSIS
##########
# Check for installed imaging engines
use OpenGL::Image;
# Get hashref of installed imaging engines
# Keys are engine names; values are versions
my $engines = OpenGL::Image::GetEngines();
# Check for a specific engine and optional version support
my $ok = OpenGL::Image::HasEngine('Magick','6.3.5');
##########
# Load texture (engine defaults to Image::Magick if not specified)
my $tex = new OpenGL::Image(engine=>'Magick',source=>'test.png');
# Get GL info
my($ifmt,$fmt,$type) = $tex->Get('gl_internalformat','gl_format','gl_type');
my($w,$h) = $tex->Get('width','height');
# Optionally use native APIs
# Note: must not change image dimensions
$tex->Native->OilPaint();
# Test if power of 2
if (!$tex->PowerOf2()) return;
# Set texture
glTexImage2D_c(GL_TEXTURE_2D, 0, $ifmt, $w, $h, 0, $fmt, $type, $tex->ptr());
##########
# Modify GL frame
my $frame = new OpenGL::Image(width=>$width,height=>$height);
# Get default GL info
my($def_fmt,$def_type) = $tex->Get('gl_format','gl_type');
# Read frame pixels
glReadPixels_c(0, 0, $width, $height, $def_fmt, $def_type, $frame->ptr());
# Sync cache
$frame->Sync();
# Modify frame pixels
$frame->Native->Blur();
# Draw back to frame
glDrawPixels_c(0, 0, $width, $height, $def_fmt, $def_type, $frame->ptr());
##########
# Save GL frame
my $image = new OpenGL::Image(width=>$width,height=>$height);
# Read frame pixels
glReadPixels_c(0, 0, $width, $height, $def_fmt, $def_type, $image->ptr());
# Save file - automatically does a Sync before write
$image->Save('MyImage.png');
##########
# Get/Set normalized pixels
my($r,$g,$b,$a) = $img->GetPixel($x,$y);
$img->SetPixel($x,$y, 1.0, 0.5, 0.0, 1.0);
# Sync cache after done modifying pixels
$frame->Sync();
##########
# Methods defined in OpenGL::Image::Common:
# Get native engine object
my $obj = $img->Native;
$obj->Quantize();
# Alternately:
$img->Native->Blur();
# Test if image width is a power of 2
if ($img->IsPowerOf2())
# Test if all listed values are a power of 2
if ($img->IsPowerOf2(@list))
# Get one or more parameter values
my @values = $img->Get(@params);
# 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();
##########
# 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 and Methods defined in engine modules:
# Get engine version
my $ver = OpenGL::Image::ENGINE_MODULE::EngineVersion();
# Sync the image cache after a write.
# Used by some engines for paged caches; otherwise a NOP.
$img->Sync();
# Save the image to a file.
$img->Save('MyImage.png');
# Get image blob.
my $blob = $img->GetBlob(type=>'png');