Shader "Custom/Equirectangular" {
Properties {
_Color ("Main Color", Color) = (1,1,1,1)
_MainTex ("Diffuse (RGB) Alpha (A)", 2D) = "gray" {}
}
SubShader{
Pass {
Tags {"LightMode" = "Always"}
Cull Front
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma fragmentoption ARB_precision_hint_fastest
#pragma glsl
#pragma target 3.0
#include "UnityCG.cginc"
struct appdata {
float4 vertex : POSITION;
float3 normal : NORMAL;
};
struct v2f
{
float4 pos : SV_POSITION;
float3 normal : TEXCOORD0;
};
v2f vert (appdata v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.normal = v.normal;
return o;
}
sampler2D _MainTex;
#define PI 3.141592653589793
inline float2 RadialCoords(float3 a_coords)
{
float3 a_coords_n = normalize(a_coords);
float lon = atan2(a_coords_n.z, a_coords_n.x);
float lat = acos(a_coords_n.y);
float2 sphereCoords = float2(lon, lat) * (1.0 / PI);
return float2(1 - (sphereCoords.x * 0.5 + 0.5), 1 - sphereCoords.y);
}
float4 frag(v2f IN) : COLOR
{
float2 equiUV = RadialCoords(IN.normal);
return tex2D(_MainTex, equiUV);
}
ENDCG
}
}
FallBack "VertexLit"
}
I'm a beginner and I had to do a lot just to understand this thread. This is what worked for me. I just combined the answers and put it in one script. I'm pretty sure I will forget this in a few weeks time, so putting it here for posterity.
Shader "Custom/Equirectangular" {
Properties {
_Color ("Main Color", Color) = (1,1,1,1)
_MainTex ("Diffuse (RGB) Alpha (A)", 2D) = "gray" {}
}
SubShader{
Pass {
Tags {"LightMode" = "Always"}
Cull Front
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma fragmentoption ARB_precision_hint_fastest
#pragma glsl
#pragma target 3.0
#include "UnityCG.cginc"
struct appdata {
float4 vertex : POSITION;
float3 normal : NORMAL;
};
struct v2f
{
float4 pos : SV_POSITION;
float3 normal : TEXCOORD0;
};
v2f vert (appdata v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.normal = v.normal;
return o;
}
sampler2D _MainTex;
#define PI 3.141592653589793
inline float2 RadialCoords(float3 a_coords)
{
float3 a_coords_n = normalize(a_coords);
float lon = atan2(a_coords_n.z, a_coords_n.x);
float lat = acos(a_coords_n.y);
float2 sphereCoords = float2(lon, lat) * (1.0 / PI);
return float2(1 - (sphereCoords.x * 0.5 + 0.5), 1 - sphereCoords.y);
}
float4 frag(v2f IN) : COLOR
{
float2 equiUV = RadialCoords(IN.normal);
return tex2D(_MainTex, equiUV);
}
ENDCG
}
}
FallBack "VertexLit"
}
