Question by udeveloping · Jun 26, 2020 at 03:03 PM · 2d game shader programming 2d sprites shader writing

2D pixel water shader

Hello! I am stuck in shader coding! i don't know nothing about, so, i have tried some codes and searching in google and i find a shader and i have edited it, the water move is fine for me, but the shader is filling alpha pixels with opaque pixels. how can i do to a shader keep transparent pixels and never override them by opaque one? Please help!

Here are the water sprite used as a tile: sprite image for tiles

and a screenshot to see the result:

This is how it should be, the desired looks (with the shader movemente): alt text

This is the code:

 Shader "Unlit/Water2D2"
 {
     Properties
     {
         _MainTex("Texture", 2D) = "white" {}
         _ScrollX("X Scroll Speed", Range(-10, 10)) = 0
         _WaveSpeed("WaveSpeed", Range(0, 100)) = 10
         _FrequencyX("X Axis Frequency", Range(0, 100)) = 34
         _AmplitudeX("X Axis Amplitude", Range(0, 100)) = 0.005
     }
         SubShader
         {
             Tags {"Queue" = "Transparent" "RenderType" = "TransparentCutOut" }
             LOD 200
 
             Pass
             {
                 CGPROGRAM
                 #pragma vertex vert
                 #pragma fragment frag
                 #pragma alpha
 
                 #include "UnityCG.cginc"
 
                 struct appdata
                 {
                     float4 vertex : POSITION;
                     float2 uv : TEXCOORD0;
                 };
 
                 struct v2f
                 {
                     float2 uv : TEXCOORD0;
                     float4 vertex : SV_POSITION;
                 };
 
                 sampler2D _MainTex;
                 float4 _MainTex_ST;
                 fixed _ScrollX;
                 fixed _FrequencyX;
                 fixed _AmplitudeX;
                 fixed _WaveSpeed;
 
                 v2f vert(appdata v)
                 {
                     v2f o;
                     o.vertex = UnityObjectToClipPos(v.vertex);
                     o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                     return o;
                 }
 
                 fixed4 frag(v2f i) : SV_Target
                 {
                     fixed time = _Time * _WaveSpeed;
                     fixed2 uvs = i.uv;
                     fixed offset = (_ScrollX * _Time);
                     uvs.y += offset;
                     uvs.y = fmod(uvs.y, 1);
                     uvs.y += sin(uvs.y * _FrequencyX + time) * _AmplitudeX;
                     fixed2 uvs2 = i.uv;
                     uvs2.y -= offset;
                     uvs2.y = fmod(uvs2.y, 1);
                     if (uvs2.y < 0)
                         uvs2.y += 1;
                     uvs2.x = 1 - i.uv.y;
                     uvs2.y += sin(uvs2.y * _FrequencyX + time) * _AmplitudeX;
                     fixed4 col = tex2D(_MainTex, uvs);
                     fixed4 col2 = tex2D(_MainTex, uvs2);
                     //?????
                     col.a = 0.5f;
                     col2.a = 0.5f;
                     col = (col + col2) / 2;
                     return col;
                 }
 
                 ENDCG
             }
         }
 }

Am i missing some pragma or setting in the code?

Add comment