| DisplaceX |
Function
The DisplaceX function is a general purpose warping tool that is similar to WarpX, except you can access a second warping image to control the distribution of a warp. Any formula can be entered in the x and y fields for custom warps. You can also create multiline expressions in this function.
|
Parameters
|
Type
|
Defaults
|
Function
|
| oversampling |
int
|
1 | The actual number of samples per pixel equals this number squared. For better antialiasing, increase the number. |
| x,yExpression |
float
|
x, y |
The expression for where the pixel information is pulled from. Expressions of x and y return the same image. Expressions of x+5, y+5 will pull the color from the pixel 5 units up and to the right of the current pixel. You can access the values of the warping image (the second one) with r,g,b,a, and z. Example expressions: |
| x,yDelta |
float
|
0, xDelta | They set the maximum distance that any pixel is expected to move, but doesn't actually move it. From any given pixel, it may be affected by any pixel within the Delta distance. This means it has to consider a much greater amount of pixels that possibly may effect the currently rendered pixel. This is bad. However, if you set a Delta value to too small an amount, you will get errors if your expression tells the pixel to move beyond that limit. Therefore, it always takes some testing to balance between speed with errors, or accuracy with drastically slower renders. Our advice: start small and increase the size until the errors disappear. |
Synopsis
image DisplaceX( image, image, int oversampling, float expression xExpression, float expression yExpression, int xDelta, int yDelta );
Script
image = DisplaceX(
image,
image,
oversampling,
xExpression,
yExpression,
xDelta,
yDelta
);
For multi-line expressions:
image = DisplaceX(
image,
image,
oversampling,
{{ xExpr1, xExpr2, ... xExprN }},
yExpression,
xDelta,
yDelta
);
Command Line
shake -displacex oversampling xExpression etc...