Cycling 74 » Topic: [5] pictslider and mask

[5] pictslider and mask

jvkr — Wed, 07 May 2008 18:35:39 +0000

This patch

– Pasted Max Patch, click to expand. –

draws an image that could be used for pictslider, and which result should be a floating red circle, with “Transparent Background” and “Has Image Mask” enabled. But the result is a red circle with a black square frame, as if something went wrong with applying the mask.

Moreover, above patch shows there’s a problem with LCD and writing images. Although the object’s size is 72×48, it writes an images that appears to be 128×128.

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johan

Re: [5] pictslider and mask

jvkr — Wed, 07 May 2008 18:51:45 +0000

In addition to this, when saving the content to lcd.png and using that for pictslider, it will actually use a file called lcd.png in the path Max5/Cycling’74/docs/refpages/max-ref/images. This points to a problem with duplicate names in the search path.

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johan

Re: [5] pictslider and mask

David Zicarelli — Thu, 08 May 2008 08:28:03 +0000

Actually, transparent background was not set in the lcd object in the example you supplied.

When transparent background is set, and I read the file produced by the writepict message to LCD into Photoshop, it definitely has a transparent background.

pictslider will work better if you forget about the mask feature and just use an image with an alpha channel. It actually creates an alpha channel from the mask, since masks are largely obsolete now, and if you try to use an image that already has an alpha channel, nothing will work correctly. “Has image mask” should be considered a compatibility mode feature only.

Since lcd can only write PNG files, and they always have alpha channels, you should just make red circles against a transparent background if that’s what you want.

For the next update, the LCD picture size will be correct for small sizes, and the image files in the documentation folder will not be in the search path. Thanks for pointing out these problems. I will also make sure the mask to alpha conversion is working properly for image files that do not contain alpha channels.

David Z.