Creating a basic planet shader for mobile

[wwWwwwW1]

@Cato11

Will it run smooth on mobile devices?

I think it will, and so do old (Built-In ages) mobiles.

[Cato11]

@wwWwwwW1

Hi, this is because of pow(0, 0).

We should try not to set “_Power” to 0 (try something like 0.001), to avoid the worst case (NaN, can cause big problem when using post-processing).

To support disabling atmosphere (and even runtime), we can add a toggle.

you may try this:

…

Thanks for the tips. I tried doing those changes but for some reason it’s giving me an error when I enable the toggle. The planet disappears and I get this error:

Metal: Error creating pipeline state (Custom/CloudedSurface): Fragment input(s) user(TEXCOORD3) mismatching vertex shader output type(s) or not written by vertex shader
(null)

Pretty sure I copied it correctly so not sure why it’s returning an error.

UPDATE: TEXCOORD3 corresponds to my worldPos inside v2f.

[wwWwwwW1]

@Cato11

user(TEXCOORD3)

Maybe can try this:

v2f structure:

struct v2f
{
    float4 pos : SV_POSITION;
    float2 uv : TEXCOORD0;
    float3 normal : NORMAL;
#if defined(_RIM_ENABLED)
    float3 worldPos : TEXCOORD1;
#endif
    float2 cloudUV : TEXCOORD2;
};

[Cato11]

@wwWwwwW1

Maybe can try this:

v2f structure:

struct v2f
{
    float4 pos : SV_POSITION;
    float2 uv : TEXCOORD0;
    float3 normal : NORMAL;
#if defined(_RIM_ENABLED)
    float3 worldPos : TEXCOORD1;
#endif
    float2 cloudUV : TEXCOORD2;
};

Unfortunately that seems to have made no difference… still the same error.

[wwWwwwW1]

@Cato11

still the same error

Sorry that I edited the code (#20) while you changing the shader.

@wwWwwwW1

Edited: use “multi_compile” instead of “multi_compile_fragment”.

Are you using "#pragma multi_compile_fragment"?

It should be "multi_compile" because I forgot that it also appears in vetex shader.

[Cato11]

@wwWwwwW1

Sorry that I edited the code (#20) while you changing the shader.

Are you using "#pragma multi_compile_fragment"?

It should be "multi_compile" because I forgot that it also appears in vetex shader.

That fixed it! Thanks so much buddy… you literally solved all my issues. I cannot thank you enough.

EDIT: I think I will rename the title of this thread to reflect the contents more accurately, so others can find it useful.

[Cato11]

Hi @[wwWwwwW1]( Creating a basic planet shader for mobile members/wwwwwww1.8413720/), I’ve been making a lot of great assets with your tips so a big thanks again. I have run into an issue though and I was wondering if you might know what is going on?

Sometimes when I move the camera about my scene, the visuals of the atmosphere shader become distorted. For example please below:

^ Here you can see the atmosphere shader is displaying a nice subtle glow around the edges, as expected.

But if I move my camera about:

^ For some reason, you can see the effect is distorted, as a solid blue overlay has appeared. This gets larger and worse the more I move the camera. Please note that literally all I did is move the camera, I did not change anything related to the shader.

Do you know why this is happening? I’ve tried adjusting camera settings but to no avail. I’m not sure if it’s down to the camera or the shader itself.

[Cato11]

The same thing also happens in the Scene View when moving the camera about and zooming in/out.

At a distance it looks fine (editor view):

If I simply zoom in without even changing the camera angle at all (editor view):

[wwWwwwW1]

@Cato11

If I simply zoom in without even changing the camera angle at all (editor view):

Hi, what it looks like if you uncheck “Enable Rim” (in material)?

[Cato11]

@wwWwwwW1

Hi, what it looks like if you uncheck “Enable Rim” (in material)?

Then the effect just disappears completely

[wwWwwwW1]

@Cato11

Sometimes when I move the camera about my scene, the visuals of the atmosphere shader become distorted. For example please below:

Hi, I’ve tested the shader and found that the calculation of worldPos is wrong.

To fix this, replace the following line:

o.worldPos = mul((float3x3)unity_ObjectToWorld, v.vertex.xyz);

with this:

o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;

[Cato11]

That solved the problem… thank you so much!

[Cato11]

@[wwWwwwW1]( Creating a basic planet shader for mobile members/wwwwwww1.8413720/) I think I spoke too soon. The more I test this, I think it actually has not fixed the issue. Please see example below:

This is after I changed the line that you mentioned above. Again, all I am doing here is moving the camera, nothing to do with the shader or material.

[Cato11]

By the way I should mention that my camera is Orthographic, not sure if that makes a difference? If I switch to perspective I am not seeing the same kind of distortion, so perhaps it does have something to do with it?

[wwWwwwW1]

@Cato11

my camera is Orthographic

Looks like View Direction should always be forward for orthographic camera. ( bgolus’s post )

To support orthographic camera, we can add another toggle:

[Cato11]

@wwWwwwW1

Looks like View Direction should always be forward for orthographic camera. ( bgolus’s post )

To support orthographic camera, we can add another toggle:

Dude you are a star! I fixed the issue by changing line:

float3 viewDirWS = normalize(_WorldSpaceCameraPos - i.worldPos);

to:

float3 viewDirWS = UNITY_MATRIX_IT_MV[2].xyz;

This seems to have fixed it! But I will be interested to see your solution too, as your one is probably better!

[wwWwwwW1]

It’s also based on bgolus’s 2nd suggestion, because the 1st one requires a matrix multiplication. (a bit more complex that the 2nd)

Properties:

Properties
{
    //...
    [Toggle(_USE_ORTHOGRAPHIC)] _UseOrthographic("Is Orthographic", Float) = 0.0
}

Pragma:

#pragma vertex vert
#pragma fragment frag
// 4 shader variants.
#pragma multi_compile _ _RIM_ENABLED
// use "shader_feature" instead of "multi_compile" if you don't need changing this property at runtime.
// This can reduce total variants to 2.
#pragma multi_compile _ _USE_ORTHOGRAPHIC
#include "UnityCG.cginc"

Fragment:

fixed4 frag(v2f i) : SV_Target
{
    float dif = max(0.05, dot(i.normal, normalize(_WorldSpaceLightPos0.xyz)));
    fixed4 col = tex2D(_MainTex, i.uv);
    // Sample the cloud texture.
    fixed4 clouds = tex2D(_Clouds, i.cloudUV);
    // Cloud Texture has alpha, so we can use alpha to lerp colors.
    col = lerp(col, clouds, clouds.a);
#if defined(_RIM_ENABLED)
#if !defined(_USE_ORTHOGRAPHIC)
    // (Perspective) Calculate world space view direction.
    float3 viewDirWS = normalize(_WorldSpaceCameraPos - i.worldPos);
#else
    // (Orthographic) Get forward view vector from inverse view matrix.
    float3 viewDirWS = UNITY_MATRIX_IT_MV[2].xyz;
#endif
    // Fresnel Effect
    float fresnel = FresnelEffect(i.normal, viewDirWS, _Power);
    // Apply before lighting, so that darkness will affect Fresnel.
    col = lerp(_FresnelColor, col, fresnel);
#endif
    fixed4 result = fixed4(col.rgb * dif * _LightColor0.rgb, 1);
    return result;
}

[Cato11]

Thanks so much, it looks like your tweak matches the one I found so that is encouraging. I can only thank you again, you are awesome.

[Cato11]

I have just discovered a new technical problem with the shader…

[Cato11]

@[wwWwwwW1]( Creating a basic planet shader for mobile members/wwwwwww1.8413720/) I’m really sorry to keep bothering you but I have now discovered another technical problem with the shader.

When it is applied, if I try to rotate the object in the axis of the camera, everything works fine:

But, as soon as I try to rotate the object in a different axis, i.e the x or z axis, you can see the rim effect is once again distorted:

This is a serious issue for me as my planets need to rotate in multiple axes. Any chance you know what is going wrong here?

I am thinking the problem possibly lies here:

o.normal = normalize(mul(v.normal, unity_WorldToObject).xyz);

P.S. This is teaching me how complex shaders are!