Mask then blur - Shader Help

[wicked halo]

here is a thread for anyone who's able to help, I don't want to keep cluttering the channel so moving everything here

[harsh burrow]

post your light and cutoff image

[wicked halo]

the cutoff texture is a tilemap, which is the black area you see, and the light is just a white circle that fades out the tilemap is taken as a _MainTex and the light is a 2D Light Texture node

I have a theory as to what might be causing that fracture

I think I may need to separate the UVs used for the initial light and the referenced "cutoff image" tilemap

that is what I currently have using ```csharp
void GaussianBlur_float(UnityTexture2D TextureMainTexture, UnityTexture2D TextureLight, float2 LightUV, float2 MainTexUV, float Blur, UnitySamplerState Sampler, out float4 Out_RGBA)
{
float4 col = float4(0.0, 0.0, 0.0, 0.0);
float kernelSum = 0.0;

int upper = ((Blur - 1) / 2);
int lower = -upper;

// cut out light from Texture

for (int x = lower; x <= upper; ++x)
{
    for (int y = lower; y <= upper; ++y)
    {
        kernelSum ++;

        float2 offset = float2(_MainTex_TexelSize.x * x, _MainTex_TexelSize.y * y);

        float4 tmp = TextureLight.Sample(Sampler, LightUV + offset);
        col += tmp.a * TextureMainTexture.Sample(Sampler, MainTexUV + offset).a * tmp;
    }
}

col /= kernelSum;
Out_RGBA = float4(col.r, col.g, col.b, col.a);
//Out_Alpha = col.a;

}

I don't believe this is properly cutting out my light texture

[harsh burrow]

so each square is a main texture and it's tilled to create a mask for the cutoff?

[wicked halo]

is what appears to be happening

[wicked halo]

yeah basically

however it's all stored on a tilemap

and the tilemap holds the shader material

I will send screenshots of the three step process I am hoping to achieve and I assume that'll help you visualize what I am going for better

^ Step 1, both the light texture and tilemap shown in full

^ Step 2, the tilemap cuts itself out from the light in theory producing an effect similar to as shown, however since the light isn't actually on the tilemap at all yet, it is invisible in practice.

Step 3, the blur effect is added which would then show on the tilemap which goes into the lerp function with the maintexture to mask and reveal it's texture when the blur is overlapped

[harsh burrow]

I undertand. First, does the code to cutoff work well?

[wicked halo]

there's not really a good way to know but based on the full light circle revealing the tilemap texture below it, I assume not.

I believe the blur portion works based on the image below responding to the blur effect being added

[harsh burrow]

does the output without blur look as intended?

[wicked halo]

with my "working" cutoff effect before it shouldn't show any light at all as it doesn't overlap my texture because it is cutting it off

[harsh burrow]

this part

[wicked halo]

there's not really a way to know for sure, but in theory there's no reason it wasn't working.

The light wasn't affecting the tilemap which means it is probably cutting it off

[harsh burrow]

can't you apply to alpha to look albedo to see if the cutoff is well applied?

[wicked halo]

well in theory right this image

is it "working"

and a shader will not display anything that isn't on the applied shader area right

so it would never show it if it were working correctly, however while working on it

there were a lot of ways to tell when it wasn't working

// masking out the tilemap early before cutting off etc

[wicked halo]

I am 80% confident this worked as intended

[harsh burrow]

Is the light in the good spot on this image?

[wicked halo]

no, not really, I'll draw up an example of what it should look like

it should look something like this

or that same effect

[wicked halo]

except instead of white it shows the cutout texture's actual texture with a tint of the light color

this would be after cutout and before blur, but you wouldn't be able to see this

[harsh burrow]

each square is a plane. can be empty(light blue) or full (black). The texture is sent to the shader in _MainTex. Right?

Main tex is these two?

[wicked halo]

nono the grey background shown here

[harsh burrow]

so it a back ground

[wicked halo]

yeah

[harsh burrow]

black or nothing

[wicked halo]

that is errelevant

main tex is

maintex looks like this

not the middle part

[harsh burrow]

gray = 0 alpha?

[wicked halo]

this is maintex

yes

and all of the maintex area would be 1 alpha

[harsh burrow]

So Light tex - gray zone of Main tex and blur the result.

[wicked halo]

so it would be here let me get them side by side

main tex is on the left and on the right is the light which is a part of the "2D Light Texture" Node

which grabs all visible lights on the screen and converts them to a texture

so then you would cut out any of the light texture with an alpha that overlaps with "MainTex"

then blur that and use any of the blur that afterwards overlaps with maintex to mask over maintex and reveal maintex's texture

so this is what it would look like after being cut out

then blurring that would make it bigger so it would overlap again

and it would hopefully give a result like this

[harsh burrow]

(ignore the green and orange), so this would be the result before the blur?

[wicked halo]

the opposite

so it would only leave the middle area light

[wicked halo]

yes exactly that

[harsh burrow]

ok I see

[wicked halo]

then that would blur and any overlap with the main texture would mask out and reveal it's texture

[harsh burrow]

ok

[harsh burrow]

this?

[wicked halo]

Yes! Very close to that, except the middle part shouldn't be shown but I assume that is just because "volumetric lighting" is enabled

also is your scene in 3d?

[harsh burrow]

I tried on my 3d project, should be the same

[wicked halo]

oh I see

[wicked halo]

perfect!

you are a legend.

[harsh burrow]

let me clean a bit

[wicked halo]

okay sounds perfect! Is that still using a custom script?

[harsh burrow]

void GaussianBlur_float(UnityTexture2D TextureMainTexture, UnityTexture2D TextureLight, float2 LightUV, float2 MainTexUV, float Blur, UnitySamplerState Sampler, out float4 Out_RGBA)
{
float4 col = float4(0.0, 0.0, 0.0, 0.0);
float kernelSum = 0.0;

int upper = ((Blur - 1) / 2);
int lower = -upper;

// cut out light from Texture

for (int x = lower; x <= upper; ++x)
{
    for (int y = lower; y <= upper; ++y)
    {
        kernelSum ++;

        float2 offset = float2(_MainTex_TexelSize.x * x, _MainTex_TexelSize.x * y);

        float4 tmp = TextureLight.Sample(Sampler, LightUV + offset);
        col += tmp.a * (1 - TextureMainTexture.Sample(Sampler, MainTexUV + offset).a) * tmp;
    }
}

col /= kernelSum;
Out_RGBA = float4(col.r, col.g, col.b, col.a);
//Out_Alpha = col.a;

}

I think it the same one as we did before

[wicked halo]

oh okay perfect

it looks the same

I have just been struggling to get it to work I am quite new to shaders in general so I don't understand UVs all too well.

[harsh burrow]

Oh yeah

(1- sampler main tex)

was the modification

[wicked halo]

oh I see that yeah

[wicked halo]

do the UVs still need to be split on the left side?

or can they share one

[harsh burrow]

Can split, I guess?

[wicked halo]

okay! I'll try this out and let you know in a sec

Hmm, it still doesn't seem to work

this is a section in my previous script where I would lerp the values of my light and my maintex to mask it with a color of my choice so maybe that needs to be implemented? But I'm really unsure

[wicked halo]

also in your shader graph all your visuals are very clear, is that just because you are using a custom mask texture or is there a setting I can enable?

[harsh burrow]

Try one thing before

sample the light and put the rgb out put on albedo

[wicked halo]

like the light texture?

[harsh burrow]

yes

just to see what it look like before everyting

[wicked halo]

this is without a screen position uv

which I think is necessary to get the tilemap to act as a whole

this is if I add a "screen position" UV

[harsh burrow]

try to use this image for the light

just to see if the blur work

[wicked halo]

Alright

do you want me to do it the same way just straight into the albedo

or with the whole shader

[harsh burrow]

in the light tex blur fonction

[wicked halo]

okay

do you know how I use that directly in the shader graph?

when I drag it in it locks it to a sample texture 2d node

nevermind

I got it

[harsh burrow]

drop the image in the shader graph

[wicked halo]

so test this?

[harsh burrow]

yes

[wicked halo]

this gives the same result as before

[harsh burrow]

is the donut one texture?

[wicked halo]

it's the _MainTex

[harsh burrow]

ok

try my asset

[wicked halo]

just your shader?

[harsh burrow]

what is this?

[wicked halo]

my donut with your shader

somehow

[harsh burrow]

show me the preview of the main text sampler node

[harsh burrow]

of your shader

[wicked halo]

yours looks the same when I remove the default

[harsh burrow]

your donut isn't one big texture but look of small game object with the same mat?

[wicked halo]

if you want you can test using the same

if you get a 2d project

it's a tilemap but you can paint "tiles" inside

[harsh burrow]

yeah

[wicked halo]

so they all have the same mat

if you make a 2d project

I can give the same tiles so you can replicate the scene 1-1

[harsh burrow]

one last thing to try

a different approach

[wicked halo]

okay!

[harsh burrow]

get the distance between light and pixel, apply inverse square law with the distance.

[wicked halo]

I can't do this

I spent like 20 hours doing that and it's super laggy

[harsh burrow]

I see

[wicked halo]

I think this approach is good

something small is breaking it I think

it's really finnicky

[harsh burrow]

yes, the problem is

you main tex doesm't have any transparentcy

[wicked halo]

oh

isn't by default the alpha 1?

[harsh burrow]

your main tex is only a small part but the light text is the whole area

[wicked halo]

and if not can we not set it

[wicked halo]

what if we use a screen position on both the tex and light

so they are lined up based on size on screen

okay wait

I might have got something working

I need to lerp it with the black color to test it fully

screen position on just the light UV and nothing on the main uv

the problem is that everything is white and I can only see the edge of the tilemap because of it's texture

[harsh burrow]

yes

can you get a coin of the light with the uvs?

[wicked halo]

this used to show the light idk why it's not atm

I had to make a new scene to fix it last time

that could be the reason

because this isn't displaying light atm for some reason

[harsh burrow]

you can use the point light png to debug instead

[wicked halo]

I can't really move it

it's not a good representation of how the light works because it won't be parsed the same way the texture 2d node would be

[harsh burrow]

if you can get the small portion of the light, then blur it and add on the main tex. You would have the same effect

maybe?

[wicked halo]

well that's what the cutout part does

then the idea is to blur it

[harsh burrow]

you don't need the cutout because every tile are in the dark section.

[wicked halo]

I do need the cutout

[harsh burrow]

hmm, I will create a 2d project and comeback

[wicked halo]

if I have no cutout then it will spill overtop everything no matter what

I can barely think I've been working at this for like 25 hours haha

[harsh burrow]

i feel you

[wicked halo]

if you make a 2d urp project on unity 2022.3.25f1 or just any recent version

and setup urp then make a tilemap I can show you how to replicate my scene fully

[harsh burrow]

loading... I will go eat something meanwhile

[wicked halo]

okay, thank you!

this is my closest attempt

but I don't think it's really cutting anything out

however the blur is working

I can increase the blur, but if I make it high it slides the light to the right

but that's not too important right now

I can probably fix that later

[harsh burrow]

well, if you are really stuck at this. You can send me the asset for me to look when I have free time.

Godspeed

[wicked halo]

it's basically just a tilemap with a square tile painted over it to make that shape with the shader applied

the texture is kinda irrelevant as it is just revealed based on the light

but yeah this is a really rough one haha

I do really appreciate all your help thusfar, I think I am just also really tired right now so I am not very helpful haha.

You're a legend 🫂

[harsh burrow]

Thank you. Sleep well and good luck.

[wicked halo]

thanks you too! I'll let you know if I get it working!

[wicked halo]

Mask then blur - Shader Help

[analog oyster]

Hi there, idk if I'm allowed to share zips on here. This is a really brittle project. I think the Kawase Blur isn't happy with my rendertexture approach (and I can't say I am either lol) but you can see for yourself how you might implement something like this w/ scriptable render passes here:

https://drive.google.com/file/d/1aKCA5INhGoVFhjd1jvceOTgP0EUw9q8i/view?usp=drive_link

If it appears black at first its because the Kawase is acting up and you just need to run the scene.

I made it for 2022.3.21f1

Scene view doesn't work either lol

but if you add things to the light layer it will blur them and multiply them w/ the shadows in the scene

control the blur here

gradually increasing blur

omg realized i rushed this out and made a mistake -- its too late in the night to fix rn but the additive shader needs to change from

Blend OneMinusDstColor One to Blend SrcAlpha One

on line 20

in Sprite-Additive.shader

It'll give your sprites form again lol

Ah! One more thing to consider is that this blur approach might not handle zooming in and out so you'll need to think a bit about that. One way to handle it would be to have the blurring camera be a constant size.

[wicked halo]

Oh my gosh, thank you so much! I'll have a look at that today, I didn't even think to check this thread until now. You are the best.

I'm so sorry for the lack of response until now, but holy I really appreciate it.

[wicked halo]

I just went over the system and I am so very thankful for these wonderful ideas, I am so extremely appreciative of you taking the time to do all this. I'll definitely try to employ some of these ideas into my lighting system as they seem very applicable to creating the ideal system I was going for. Truly an amazing person and I really appreciate your work here much love <3 🫂

[analog oyster]

Good luck!! These posts feel like little puzzles to me. This one jumped out bc I haven't thought too much about 2D. Glad the ideas are helpful!

[wicked halo]

Haha I know exactly what you mean, I used to do the same thing with python.