[cairo] Image blending question

[Homer Mu]

I apologize if this is a super newbie question, but I am having trouble with basic blending. So far I have had success (and a lot of fun!) with basic compositing of images, text, and paths / filled paths. However, whenever I have overlapping objects with varying opacity, I struggle with the way the images blend. What I want to achieve is sort of a cross-disolve type blending (such as what you would see in a slide show screensaver). But my results are full of widly varying brightness levels. The blending is probably working as designed, but I just can't figure out how to blend in a way that maintains the original image brightness. I have tried many of the composting operators (CAIRO_OPERATOR_DEST_OVER, etc) without much success. Any advice or examples for this type of super basic blending would be greatly appreciated!! Thank you in advance for any help! HM
 		 	   		  
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