125 lines
4.0 KiB
GLSL
125 lines
4.0 KiB
GLSL
Shader "DBV/Kristo/InstancedGrassShader"
|
|
{
|
|
Properties {
|
|
_MainTex("Albedo (RGB)", 2D) = "white" {}
|
|
_Glossiness("Smoothness", Range(0,1)) = 0.5
|
|
_Metallic("Metallic", Range(0,1)) = 0.0
|
|
|
|
[Space]
|
|
_ColorA("Color A", Color) = (1,1,1,1)
|
|
_ColorB("Color B", Color) = (1,1,1,1)
|
|
|
|
[Space]
|
|
_AlphaCutoff ("Alpha cutoff", Range(0,1)) = 0.05
|
|
}
|
|
SubShader
|
|
{
|
|
Tags { "RenderType"="Instanced" }
|
|
LOD 200
|
|
Cull Off
|
|
|
|
CGPROGRAM
|
|
#pragma surface surf Standard vertex:vert //addshadow
|
|
#pragma multi_compile_instancing
|
|
#pragma instancing_options procedural:setup
|
|
|
|
#pragma target 4.5
|
|
|
|
sampler2D _MainTex;
|
|
|
|
struct Input{
|
|
float2 uv_MainTex;
|
|
};
|
|
|
|
struct GrassElement {
|
|
float3 position;
|
|
float rotation;
|
|
float size;
|
|
float colorBlend;//0-1
|
|
};
|
|
|
|
//Note
|
|
//StructuredBuffers are good when there are loads of data that needs to be read at different places by different threads
|
|
//Constant buffers are good when there isent too much data and threads read the same data
|
|
|
|
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
|
|
StructuredBuffer<GrassElement> grassBuffer;
|
|
#endif
|
|
|
|
|
|
//https://forum.unity.com/threads/rotating-mesh-in-vertex-shader.501709/
|
|
float3x3 YRotationMatrix(float degrees) {
|
|
float alpha = degrees * UNITY_PI / 180.0;
|
|
float sina, cosa;
|
|
sincos(alpha, sina, cosa);
|
|
return float3x3(
|
|
cosa, 0, -sina,
|
|
0, 1, 0,
|
|
sina, 0, cosa);
|
|
}
|
|
//USAGE: pos.xyz = mul(YRotationMatrix(degrees),pos.xyz);
|
|
|
|
void rotate2D(inout float2 v, float r) {
|
|
float s, c;
|
|
sincos(r, s, c);
|
|
v = float2(v.x * c - v.y * s, v.x * s + v.y * c);
|
|
}
|
|
|
|
half _Glossiness;
|
|
half _Metallic;
|
|
fixed4 _ColorA, _ColorB;
|
|
float _AlphaCutoff;
|
|
|
|
void setup () {
|
|
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
|
|
GrassElement data = grassBuffer[unity_InstanceID];
|
|
//Scale the mesh
|
|
unity_ObjectToWorld._11_21_31_41 = float4(data.size, 0, 0, 0);
|
|
unity_ObjectToWorld._12_22_32_42 = float4(0, data.size, 0, 0);
|
|
unity_ObjectToWorld._13_23_33_43 = float4(0, 0, data.size, 0);
|
|
//position the mesh
|
|
unity_ObjectToWorld._14_24_34_44 = float4(data.position.xyz, 1);
|
|
|
|
//No idea what this does
|
|
unity_WorldToObject = unity_ObjectToWorld;
|
|
unity_WorldToObject._14_24_34 *= -1;
|
|
unity_WorldToObject._11_22_33 = 1.0f / unity_WorldToObject._11_22_33;
|
|
#endif
|
|
}
|
|
|
|
void vert (inout appdata_full v) {
|
|
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
|
|
GrassElement data = grassBuffer[unity_InstanceID];
|
|
//Rotate
|
|
v.vertex.xyz = mul(YRotationMatrix(data.rotation),v.vertex);
|
|
#endif
|
|
}
|
|
|
|
void surf (Input IN, inout SurfaceOutputStandard o) {
|
|
|
|
//Clip the grass
|
|
fixed4 c = tex2D (_MainTex, IN.uv_MainTex);
|
|
clip(c.a - _AlphaCutoff);
|
|
|
|
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
|
|
GrassElement data = grassBuffer[unity_InstanceID];
|
|
|
|
float blend = data.colorBlend;
|
|
fixed4 col = blend * _ColorA + (1-blend) * _ColorB;
|
|
#else
|
|
fixed4 col = _ColorA;
|
|
#endif
|
|
|
|
// Albedo comes from a texture tinted by color
|
|
c = c * col;
|
|
o.Albedo = c.rgb;
|
|
// Metallic and smoothness come from slider variables
|
|
o.Metallic = _Metallic;
|
|
o.Smoothness = _Glossiness;
|
|
o.Alpha = c.a;
|
|
}
|
|
ENDCG
|
|
}
|
|
FallBack "Diffuse"
|
|
}
|