RotateBicubic rotates wrong direction.

zhaojiahai / aforge

Automatically exported from code.google.com/p/aforge

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What steps will reproduce the problem?
1. I was using the RotateBicubic class.
2. Rotate using a negative angle.

What is the expected output? What do you see instead?
The image rotated counter clockwise rather than clockwise. 
RotateNearestNeighbor and RotateBilinear both rotate clockwise with a 
negative angle, so this was an inconsistency.

What version of the product are you using? On what operating system?
Latest version under source control. Vista.

Please provide any additional information below.

This is the line of code I changed to fix it.
Should be around line 122.
//Fixed because -angle should rotate clockwise
//dx = ox - (double) ox1;
//dy = oy - (double) oy1;
dx = (double)ox1 - ox;
dy = (double)oy1 - oy;

Original issue reported on code.google.com by MichaelL...@gmail.com on 13 Oct 2008 at 3:36

There must be some sort of confusion. All 3 rotation filters rotate in the same direction, which counterclockwise. The counterclockwise was chosen intentionally – filter accepts angle in polar coordinates system (actually in Cartesian system angles are measured also in counterclockwise direction).

zhaojiahai / aforge

RotateBicubic rotates wrong direction. #74