Blur active object

[kikiriki]

Hi guys!

Is it possible to blur (and unblur) active object during the runtime?

If yes- I would appreciate an example. :-)

Thank you in advance
Dusan

[LB]

I am pretty sure you can do it with a pixel shader in the HWA runtime. Or you might be able to use the lens object

[kikiriki]

Thank you LB!
I downloaded "Complex-shaders Pack V2", which looks exactly what I need. First I tried "Simple Blur" Effect which has only one parameter: "fCoeff". It worked fine, but the end result was not what I expected

So I tried "Blur Real", which has two parameters: "fCoeff" and "nSteps". I tried with numerous values for both parameters, but this time I didn't see any effect on the active object.

Can please someone explain how this effect works?

[Pixelthief]

the "Blur" pixel shaders work by creating multiple semitransparent copies of the image and displacing them from each other. A "2x" blur will create 2 images, and displace them. A "4x" blur will create 4 images. Generally these are aligned on equal angles.

The "nSteps" blur effect uses an integer "N" amount of blur images. The fCoeff parameter refers to how far these images are displaced from on another.


If you are looking for a blur effect that actually stretches or deforms an image, you'll need to use a different pixel shader, or better yet, make one yourself (exactly what I've done when I need one!)

[kikiriki]

Pixelthief, thank you very much!

As I mentioned both parameters doesn't give any effect on the object. I'm attaching a short MFA file- would you be so kind to check what I'm doing wrong?

link: blur_shader.mfa

Unfortunately I don't have enough knowledge to write my own blur shader! But if I understand you correctly, you wrote one? Would you be so kind to share it?

[Pixelthief]

Using the "Set effect" action will reset all parameters on the object. In your code, you are only setting either the fCoeff or the nSteps parameters, not both, at the same time.


It appears that this shader uses 4^N or so images, if I'm reading it right, by recursively drawing the image from each of 4 nodes to the immediate north, south, east, and west. So not exactly the "rotate around the image" I would have guessed.

[kikiriki]

Pixelthief, thank you very much!!! Yes, that was the problem- It works now! :-)

But you are right- I'm a little disappointed on quality. You need quite a big "nSteps" factor if you want a decent results. And this slows down the program significantly! (I have 10 objects in the scene which needs to be blurred). And I have a feeling that this objects doesn't work well with alpha channel.

So if anybody knows a better solution, I will be very thankful :-)