Gecko:Image Snapping and Rendering: Difference between revisions

Gecko:Image Snapping and Rendering (view source)

480 bytes added , 13 November 2008

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 === Requirement 8 ===
-Requirement 8 is difficult to prove.
+Requirement 8 is difficult to prove. Here's the proof. We'll consider just one axis and show that the device pixel fill rectangle, transformed to image space, intersects the subimage rectangle along that axis.
+The input parameters:
+* Let H be the image dimension in pixels
+* Let D1 and D2 be the start and end of the initial rectangle in device space
+* Let F1 and F2 be the start and end of the logical fill rectangle in device space
+* Let A be the anchor point in image space
+We require H > 0, D1 < D2 and F1 < F2.