Monks,

I'm done some text manipulation in perl, but I'm QUITE new to working with images and I've run into a bit of a problem. I'm just testing out some of the basic draw functions with the GD module that I'd like to use on a bigger more complex program. Start simple right? This is just supposed to draw an image and have the color go black to red on the x axis and black to green on the y axis.

The real problem I have is in the output of the picture (can be seen here: http://www.jasonmmoffett.com/alan_temporary/picture.png) Basically, about 1/3 of the way through scaling the x, the colors mess up. Is there a limit to the number of colors that can be defined with colorAllocate? Is there an easier way which you can define specific colors other than using a ton of colorAllocate calls? I dropped the actual number of colors used down because it was taking so long to run. Maybe a different drawing package all together would work better? Maybe I should try my hand in C? Really, I just need to be able to define colors based on equation output on a pixel by pixel basis. So I could have a script color any pixel in the image say 8-bits worth of color, or however many.

The code is below.

Thanks for your time!

-Alan 

#!/usr/bin/perl

#use strict;
use GD;

$width = 800;
$height = 600;

$outpizzle = new GD::Image($width,$height);
#$outpizzle->interlaced('true');

#define a $%!@ ton of colors ... bad idea?
for ($i=0; $i<10; $i++) {
    for ($j=0; $j<10; $j++) {
        for ($k=0; $k<10; $k++) {
            $colors[$i][$j][$k] = $outpizzle->colorAllocate($i*25,$j*2
+5,$k*25);
        }
    }
}

#draw some shizzle
for ($i=0; $i<$width; $i++) {
    for ($j=0; $j<$height; $j++) {
        $outpizzle->setPixel($i,$j,$colors[int(10*($i/$width))][int(10
+*($j/$height))][0]);
        #print int(10*($i/$width))+"\n";
    }
}

#output the picture
open(PICTURE, ">picture.png") or die("uh oh spaghettio");
binmode PICTURE;
print PICTURE $outpizzle->png;
close PICTURE;

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In reply to Image Editing with GD by alanonymous

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