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Template Questions /

Moderators: martimiz, Sean, Ed, biapar, Willr, Ingo, swaiba

Using GD resize() on Image objects in a page controller


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2 Posts   3116 Views

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david_nash

Community Member, 55 Posts

18 March 2009 at 6:33pm

I'm writing a function that selects an image at random and returns an image tag. I'd like to scale that image, but I can't work out how.

class HomePage_Controller extends Page_Controller {
...

  function RandomImage() {
    $galleryItem = DataObject::get_one('GalleryItem', 'MyHomePageID != 0', false, 'RAND()');
    $g = DataObject::get_by_id("GalleryItem_ProductImage", $galleryItem->GalleryItemImageID);

    //somehow scale $g here

    return "<img src=\"$g->Filename\" alt=\"$galleryItem->GalleryItemTitle\" />";	
  }

...
}

As I understand it, my get_by_id() call should be returning an Image (GalleryItem_ProductImage extends Image) which means that I should be able to use GD functions on it.

But if I create a new GD object and use resize() it, how do I then get the filename for the src attribute?

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david_nash

Community Member, 55 Posts

19 March 2009 at 1:28pm

Edited: 19/03/2009 1:30pm

Here's the workaround that I used. In mysite/code/HomePage.php.

I now have:

function RandomImage() {
	return DataObject::get_one('GalleryItem', 'MyHomePageID != 0', false, 'RAND()');
}

In my template I just wanted to have $RandomImage, which would output an <img scr="blah.jpg" alt="blah"> tag.

Instead I do this in the template:

<% if ClassName = HomePage %>
	<% control RandomImage %>
		<img src="$GalleryItemImage.Scaled.URL" alt="$GalleryItemTitle" class="Logo{$LightLogo}" >
	<% end_control %>
<% end_if %>

RandomImage() returns at GalleryItem, and I used RandomImage to "iterate" through the set of one GalleryItem.

In mysite/code/GalleryItem.php, after the GalleryItem model class I have:

class GalleryItem_ProductImage extends Image {

	function generateScaled($gd) {
		return $gd->resize(552, 561);
	}

} //end class

I'm not really sure why but this allows me to use "$GalleryItemImage.Scaled" in the template. SS chops off the 'generate' part of 'generateScaled' and 'Scaled' returns a GD object, which for some reason I don't understand I can then access its URL property.

I hope this helps someone, and I hope someone else can explain to me the things I don't understand :-)

(ps wow, tabs work in "code" blocks!)