TextMesh Pro Textmesh Pro Text clipping with custom 3D material on Android

Hi,

I'm currently trying to resolve an issue where UGUI Text Mesh Pro text is incorrectly clipping with a material using a custom shader used in the world space when displaying on android using OpenGL ES 2.0.

I'm guessing I'm missing a keyword in my shader that is causing a weird interaction with TMPro's UGUI Text. It seems to work fine in the editor, and I can see the problem when using both the regular SDF shader and the mobile SDF shader.

I have seen the problem before and managed to fix it by increasing the Material Render Queue properties on the font material, but it's stopped working today and I have absolutely no idea why.

Using Unity 2018.1.0f2

Example:

The parts of the text are disappearing when drawn in a UGUI canvas infront of 3d objects using this custom shader:

Code (CSharp):

1. Shader "Custom/Diffuse"
2. {
3.     Properties
4.     {
5.         _MainTex ("Texture", 2D) = "white" {}
6.     }
7.     SubShader
8.     {
9.         Tags { "RenderType"="Opaque" }
10.  
11.         Pass
12.         {
13.             Tags{"LightMode" = "ForwardBase"}
14.  
15.             CGPROGRAM
16.             #pragma vertex vert
17.             #pragma fragment frag
18.             #pragma multi_compile_fog
19.             #pragma multi_compile_fwdbase
20.          
21.             #pragma fragmentoption ARB_precision_hint_fastest
22.             #pragma target 2.0
23.             #pragma hardware_tier_variants gles
24.          
25.             #include "UnityCG.cginc"
26.             #include "AutoLight.cginc"
27.             #include "Lighting.cginc"
28.  
29.             struct appdata
30.             {
31.                 float4 vertex : POSITION;
32.                 float2 uv : TEXCOORD0;
33.                 half3 normal : NORMAL;
34.             };
35.  
36.             struct v2f
37.             {
38.                 float2 uv : TEXCOORD0;
39.                 LIGHTING_COORDS(1, 2) // Store the lighting coords in texcoords 0 and 1.
40.                 UNITY_FOG_COORDS(3)
41.                 float4 pos : SV_POSITION;
42.                 fixed4 vertexColour : COLOR;
43.             };
44.  
45.             sampler2D _MainTex;
46.             float4 _MainTex_ST;
47.          
48.             v2f vert (appdata v)
49.             {
50.                 v2f o;
51.                 o.pos = UnityObjectToClipPos(v.vertex);
52.                 o.uv = TRANSFORM_TEX(v.uv, _MainTex);
53.  
54.                 UNITY_TRANSFER_FOG(o,o.pos);
55.                 TRANSFER_VERTEX_TO_FRAGMENT(o);
56.  
57.                 float3 n = UnityObjectToWorldNormal(v.normal) * 0.3f;
58.                 o.vertexColour = _LightColor0 * saturate(4 * dot(n, _WorldSpaceLightPos0.xyz) + 0.1f);
59.                 o.vertexColour.a = 1;
60.              
61.                 return o;
62.             }
63.          
64.             fixed4 frag (v2f i) : SV_Target
65.             {
66.             #if !UNITY_HARDWARE_TIER1
67.                 fixed atten = LIGHT_ATTENUATION(i);
68.                 fixed4 col = tex2D(_MainTex, i.uv) * i.vertexColour * saturate(unity_AmbientSky + fixed4(atten, atten, atten, 1));
69.                 // apply fog
70.                 UNITY_APPLY_FOG(i.fogCoord, col);
71.             #else
72.                 fixed4 col = tex2D(_MainTex, i.uv) * i.vertexColour;
73.             #endif
74.                 return col;
75.             }
76.             ENDCG
77.         }
78.  
79.         UsePass "Custom/ShadowShader/SHADOWCASTER"
80.     }
81.  
82.     FallBack "Diffuse"
83. }
84.  

Thanks

 

Solved the problem through a bunch of digging around.

In my TMP_SDF-Mobile.shader file I made these changes:

At the end of the Shader Properties I added:
[Enum(UnityEngine.Rendering.CompareFunction)] unity_GUIZTestMode("ZTest", Float) = 4

In the subshader I changed:
ZTest [unity_GUIZTestMode]

To
ZTest [Always]

The bug is also reproducible on iOS.

EDIT
Making these changes causes another problem alone doesn't fix the problem. I had to change my render queue on my font material. Changing it in the editor caused text to draw over UI elements.

To fix this I made a script that when running on mobile edits render queue of the font meterial to a higher number.