Control post-processing effects parameters via code

[Lunarovich]

Hello! I know how to attach post-processing effects to a camera via editor as well as programmatically. However, I do not know how to control post-processing shader parameters dynamically.

 

For example, Shadmar's pixelate shader has this variable:

 

const int downgrade = 6; //at original 1920x1080, 6 yields 320x180

 

Now, how can I change downgrade value via Lua code?

 

Thank you!

[Rastar]

You would have to make this into a uniform

 

uniform int downgrade = 6;

 

and can then set it via Shader:SetInt().

[gamecreator]

This might help too

http://www.leadwerks.com/werkspace/topic/11762-posteffect-collection/page__st__20#entry89091

[Lunarovich]

You would have to make this into a uniform

 

uniform int downgrade = 6;

 

and can then set it via Shader:SetInt().

 

I see the point. However, if you look at the API, you'll see that Camera:AddPostEffect accepts only string. That said, I cannot first load a shader and send a reference to the shader as a parameter to the camera. Rather, I send a string and never get the reference to the shader back from camera (at least in Lua and as far as I can see).

 

 

 

This might help too

http://www.leadwerks.com/werkspace/topic/11762-posteffect-collection/page__st__20#entry89091

 

That would probably be the way to control Shadmar's shaders? But can you control stock shaders (ones that come with LE) in the same way?

[Rastar]

I see the point. However, if you look at the API, you'll see that Camera:AddPostEffect accepts only string. That said, I cannot first load a shader and send a reference to the shader as a parameter to the camera. Rather, I send a string and never get the reference to the shader back from camera (at least in Lua and as far as I can see).

 

The path parameter for Camera:AddPostEffect also accepts a Lua script which does the shader handling. I have no access to Leadwerks right now, but iirc the Bloom effect uses this approach (have a look at Shaders/PostProcess).

[Lunarovich]

The path parameter for Camera:AddPostEffect also accepts a Lua script which does the shader handling. I have no access to Leadwerks right now, but iirc the Bloom effect uses this approach (have a look at Shaders/PostProcess).

 

Thanks! It occured to me to use also this approach. However, I wanted to see if there is a more direct approach. I'm asking all this because I have an idea of a gameplay based on various postprocessing parameter manipulations - different types of subjectivities manifested via different types of vision.