koobas.hobune.stream
Gradient shader for mobile?
Where is the mistake in the code? I just want a simple basic gradient shader for mobile. I get only one color, when I use the bottom shader. Or is there a better gradient shader for mobile?
Shader "Custom/BasicGradient"
{
Properties
{
_TopColor ("Top Color", Color) = (1, 1, 1, 1)
_BottomColor ("Bottom Color", Color) = (1, 1, 1, 1)
_RampTex ("Ramp Texture", 2D) = "white" {}
}
SubShader
{
Pass
{
Blend SrcAlpha OneMinusSrcAlpha
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
struct vertexIn {
float4 pos : POSITION;
float2 uv : TEXCOORD0;
};
struct v2f {
float4 pos : SV_POSITION;
float2 uv : TEXCOORD0;
};
v2f vert(vertexIn input)
{
v2f output;
output.pos = mul(UNITY_MATRIX_MVP, input.pos);
output.uv = input.uv;
return output;
}
fixed4 _TopColor, _BottomColor;
sampler2D _RampTex;
fixed4 frag(v2f input) : COLOR
{
return lerp(_BottomColor, _TopColor, tex2D(_RampTex, input.uv).a);
}
ENDCG
}
}
}
It should look like this: 
OK, your problem is simply at this part:
return lerp(_BottomColor, _TopColor, tex2D(_RampTex, input.uv).a);
What you are interpolating is from the alpha channel of your texture, not the y - axis you want. Simply change to
return lerp(_BottomColor, _TopColor, input.uv.x);
or
return lerp(_BottomColor, _TopColor, input.uv.y);
Will show what you want. If you want to keep your texture, simply multiply this part with the texture. Besides, you can also choose to use a texture already saved with gradient alpha channel, then you no need to change anything.
