I want to use ImageMagick to edit an existing image by making some selected points a specific colour.
I am trying to use the Draw command with the ‘point’ primitive. However, I can only get a black point regardless of what colour I am trying to set.
This is shown in the Perl code below where:
1. I draw a blue rectangle;
2. Try and set a number of points to white in a rectangle that partly overlaps the blue rectangle.
However, I get black points in the rectangle.
How can I set white (and any other colour) points?
use Image::Magick;
my ($col, $img_width, $row, $img_height);
# Create a new image
my $im = Image::Magick->new(size => '400x300');
# Give it a white background
$im->Read('xc:white');
# Put a rectangle in there somewhere
$im->Draw(primitive => 'rectangle',
          points    => '0,129 199,169',
          fill      => 'blue',
          stroke    => 'blue');
for($col = 50; $col < 100; $col ++ ) {
    for ($row = 150; $row < 200; $row ++ ) {
        $im->Draw(primitive    => 'point',
        points    => "$col,$row",
        stroke    => 'white');
    }
}
$im->Write('pointquery.png');

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In reply to ImageMagick Point Query by bensonmonk

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