transform_world() and matrix

[françois leroy]

Hi!

I've got a layer effect, I get the camera matrix (which is a 4x4 matrix), and I'm trying to convert this cameraMatrix into a 3x3 matrix usable by transform_world().

I've tried to manipulate the matrix by hand with 9 floatSliders, and here's the result:

scale_X          skew_Y               ?

skew_X          scale_Y               ?

displace_X     displace_Y          ?

The ? only make stripes of empty alpha...

It seems the 3x3 matrix can only perform affine transformations... is it normal?

If so, is there any way to apply perspective transformation directly?

Thanx,

François

[shachar carmi · Accepted solution]

3x3 matrices acn only do 2D transformations.

position, scale, Z rotation and skewing. (anything the "Transform" effect does)

4x4 matirces contain more params, such as x and y roataions and z translations.

so you can't really tranlate a 4x4 matrix into a 3x3. you'll need to decompose the 4x4 matrix and re-feed it into the 3x3.

in any case, trying to create a "corner pin" sort of transform using transform_world() is not possible. (to the best of my knowldge)

[françois leroy]

Hi Shachar!

I was afraid you'd say so...

And I didn't see any way to apply 4x4 matrix transform, except for artisans....

Thanx,

François

[shachar carmi]

sometimes i'm the bearer of bad news...