So I’m attempting to create a laser pointer using a projector and a shader. My current shader works, even on self-illuminating or transparent objects, but the problem is that it multiplies the color of the projector by the color of the surface it’s on. So if the surface is black, the bright red laser pointer doesn’t show at all.
What I was wondering was if anyone here had any experience with laser pointers, or related shaders. I just need ideas for something that can shine on a given surface regardless of the surface’s existing colors.
Here’s my code for the current shader, it’s a bit outdated because I coded it in Unity4, and like I said above I’m no shader programmer so it’s probably not the best shader.
Shader "Projector/Multiply_TT" {
Properties {
_ShadowTex ("Cookie", 2D) = "gray" {}
_FalloffTex ("FallOff", 2D) = "white" {}
}
Subshader {
Tags {"Queue"="Transparent"}
Pass {
ZWrite Off
ColorMask RGB
Blend DstColor Zero
Offset -1, -1
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma multi_compile_fog
#include "UnityCG.cginc"
struct v2f {
float4 uvShadow : TEXCOORD0;
float4 uvFalloff : TEXCOORD1;
UNITY_FOG_COORDS(2)
float4 pos : SV_POSITION;
};
float4x4 _Projector;
float4x4 _ProjectorClip;
v2f vert (float4 vertex : POSITION)
{
v2f o;
o.pos = mul (UNITY_MATRIX_MVP, vertex);
o.uvShadow = mul (_Projector, vertex);
o.uvFalloff = mul (_ProjectorClip, vertex);
UNITY_TRANSFER_FOG(o,o.pos);
return o;
}
sampler2D _ShadowTex;
sampler2D _FalloffTex;
fixed4 frag (v2f i) : SV_Target
{
fixed4 texS = tex2Dproj (_ShadowTex, UNITY_PROJ_COORD(i.uvShadow));
texS.a = 1.0-texS.a;
fixed4 texF = tex2Dproj (_FalloffTex, UNITY_PROJ_COORD(i.uvFalloff));
fixed4 res = texS * texF.a;
UNITY_APPLY_FOG_COLOR(i.fogCoord, res, fixed4(1,1,1,1));
return res;
}
ENDCG
}
}
}