-
Notifications
You must be signed in to change notification settings - Fork 13
/
edgeDetection.shader
100 lines (87 loc) · 2.79 KB
/
edgeDetection.shader
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Shader "LX/edgeDetection"
{
Properties
{
_MainTex ("Texture", 2D) = "white" {}
}
SubShader
{
ZTest Always
Cull Off
Zwrite Off
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
struct appdata
{
float4 vertex : POSITION;
float2 uv : TEXCOORD0;
};
struct v2f
{
float4 vertex : SV_POSITION;
half2 uv[9]:TEXCOORD0;
};
sampler2D _MainTex;
float4 _MainTex_ST;
half4 _MainTex_TexelSize;
fixed3 edgeColor;
float threshold;
half sobel(v2f i)
{
const half Gx[9] =
{
-1, -2, -1,
0, 0, 0,
1, 2, 1
};
const half Gy[9] =
{
-1, 0, 1,
-2, 0, 2,
-1, 0, 1
};
half texColor;
half edgeX = 0;
half edgeY = 0;
for (int index = 0; index < 9; index++)
{
texColor = Luminance(tex2D(_MainTex, i.uv[index]));
edgeX += texColor * Gx[index];
edgeY += texColor * Gy[index];
}
half edge = 1 - abs(edgeX) - abs(edgeY);
return edge;
}
v2f vert(appdata v)
{
v2f o;
o.vertex = UnityObjectToClipPos(v.vertex);
half2 uv = v.uv;
o.uv[0] = uv + _MainTex_TexelSize.xy * half2(-1, -1);
o.uv[1] = uv + _MainTex_TexelSize.xy * half2(0, -1);
o.uv[2] = uv + _MainTex_TexelSize.xy * half2(1, -1);
o.uv[3] = uv + _MainTex_TexelSize.xy * half2(-1, 0);
o.uv[4] = uv + _MainTex_TexelSize.xy * half2(0, 0);
o.uv[5] = uv + _MainTex_TexelSize.xy * half2(1, 0);
o.uv[6] = uv + _MainTex_TexelSize.xy * half2(-1, 1);
o.uv[7] = uv + _MainTex_TexelSize.xy * half2(0, 1);
o.uv[8] = uv + _MainTex_TexelSize.xy * half2(1, 1);
return o;
}
fixed4 frag(v2f i) : SV_Target
{
fixed4 col = tex2D(_MainTex, i.uv[4]);
half edge = sobel(i);
if (edge > threshold)
return col;
else
return fixed4(edgeColor, 1);
}
ENDCG
}
}
}