RG Corner Pin plug-in: Reposition group

The Reposition group directly affects the pinning with secondary transforms that are applied after the To/From warp. Translate, Scale and Rotate let you make position changes after set the pins with the To/From Pins groups. They affect the input image, that is, the From Pins image.

Reposition controls are affected by Transform Settings> Grow Bounds. Pay attention to what's going on when you use any of these controls. They may seem to break the perspective of the warp that has been set. However, what's really happening is the bounding box isn't large enough to show the extra pixels built into the transform. Making the Grow Bounds value larger will fix this problem.

Note: The Crop To Pins checkbox doesn't affect on Scale, Translate or Rotate. This is because the output is defined as a bounding rectangle (or trapezoid) by the From/To points.

 

 

 

Translate X, Translate Y

Shifts the warped image (From Pins) to the left, right, top or bottom by the defined value. You can translate in X or Y directions. This transformation is applied after the warp and does not affect the target image (To Pins).

The default value is 0. The To and From values cause the input image to shift in opposite directions. For the To Pins, inputting a number over 0 will shift the pins to the right (for X) or upward. A number less than 0 will shift the pins to the left (for X) or upward (for Y).  For the From Pins, inputting a number over 0 will shift the pins to the left (for X) or downward. A number less than 0 will shift the pins to the right (for X) or downward. If cropping of the input image occurs, you can increase the Grow Bounds control to extend the bounding box of the image, and allow enough room for the full image to show.

 

Translate X at -15, Grow Bounds at 0. This pushes the Flower input image to the right but its bottom right side gets chopped off.

 

Translate X at -15, Grow Bounds at 200. This expands the Flower's bounding box and shows the entire image.

 

 

Scale X, Scale Y

Scales up or down the warped image (From Pins) by the defined value. You can translate in X or Y directions. This transformation is applied after the warp and does not affect the target image (To Pins).

If you scale up the image, this transformation breaks the perspective that was set by the plug-in pins. So if we go from a Scale X, Y of 1.0 to 1.25, the image is enlarged/stretched by 25% outside of how the warp was already defined. This is basically a way for you to set the corner pins exactly to where you want, but let's say that you want a little overlap because you don't feel the top and bottom images are an exact pin match, then you can up the size slightly to make up the gap.

The concept to wrap your head around is how the values work. The default value is 1.0. Inputting a number over 1.0 will make the image smaller. A number less than 1.0 will make the image larger. This feels a little backwards but that's the way the double warp needs to apply itself.

 

At left, Scale X and Scale Y at 1.0 (default). At right, Scale X, Y at 1.02. We had difficulty getting the input image to completely cover the output; you can see the red of the Billboard peeking out behind the Coffee Cup. Making a slight increase in the Scale value gives the Coffee Cup enough girth to cover the billboard entirely. This is a perfect use of the Scale controls.

 

Left to right: Scale X at 1.0 (default). Scale X at 0.8. Scale X at 1.2.

 

 

Rotate, value 2

Rotates the warped image (From Pins) either clockwise or counter-clockwise. This transformation is applied after the warp and does not affect the target image (To Pins). There are two values with defaults of 0, 0. As the rotation occurs, the higher the value of the rotation, the more the image appears skewered. This is because the rotation is still maintaining the perspective of the pinning.

The second value specifies the direction of the rotation. Inputting a number over 0 will rotate the image to the right. A number less than 0 will rotate the image to the left. 

 

At left, Rotate at 20. At right, Rotate at -10. The higher the rotation, the more distorted the input image appears.

 

 

Rotate, value 1

We mentioned that there are two values for Rotate, both set by default to 0. The first value sets the number of rotations for the image in the specified direction. This is used for animation purposes. In our example below, in the From Pins group, we have set the first value to 1 and the second value to 10. This means that over 30 frames, the Flower graphic will rotate clockwise for one full rotation (value 1) until it reaches a 10 degree rotated position (value 2).

 

At beginning of animation (frame 0), no rotation has happened yet.

 

At frame 20 of animation, over half a rotation cycle has been reached.

 

When frame 30 (1 second) of animation is reached, the Flower graphic has done a full rotation.