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
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
#version 410 core
/**
* @project Spring RTS
* @file bumpWaterCoastBlurFS.glsl
* @brief Input is a 0/1 bitmap where 1 indicates land. Shader
* blurs this map, resulting in a distance-to-land map
* a.k.a. coastmap.
* @author jK
*
* Copyright (C) 2008,2009. Licensed under the terms of the
* GNU GPL, v2 or later.
*/
#define res 15.0
#define renderToAtlas (args.x == 1)
#define kernelRadius (args.y)
uniform sampler2D tex0; // final (fullsize) texture
uniform sampler2D tex1; // atlas with to be updated rects
uniform ivec2 args; // .x := renderToAtlas, .y := kernelRadius
in vec4 vTexCoord;
layout(location = 0) out vec4 fFragColor;
vec2 texelScissor = vec2(dFdx(vTexCoord.p), dFdy(vTexCoord.q)); // heightmap pos
vec2 texel0 = vec2(dFdx(vTexCoord.s), dFdy(vTexCoord.t)); // 0..1
vec4 tex2D(vec2 offset) {
if (renderToAtlas)
return texture(tex0, vTexCoord.st + offset * texel0);
vec2 scissor = vTexCoord.pq + (offset * texelScissor);
// check if outside atlas bounds
if (any(greaterThan(scissor, vec2(1.0))) || any(lessThan(scissor, vec2(0.0))))
return texture(tex1, vTexCoord.st);
return texture(tex1, vTexCoord.st + offset * texel0);
}
vec2 getDistRect(float d, vec2 offset) {
float minDist = (res - d * res) * (res - d * res);
vec2 dist;
dist.x = floor(minDist);
dist.y = sqrt(minDist - dist.x * dist.x);
dist += offset;
return dist;
}
float sqlength(vec2 v) {
return dot(v, v);
}
void LoopIter(inout float maxDist, inout vec3 minDist, float i) {
// 0____1____2
// | |
// | |
// 3 x 4
// | |
// | |
// 5____6____7
vec4 v1, v2;
v1.x = tex2D(vec2(-i, kernelRadius)).g;
v1.y = tex2D(vec2( i, kernelRadius)).g;
v1.z = tex2D(vec2(-i, -kernelRadius)).g;
v1.w = tex2D(vec2( i, -kernelRadius)).g;
v2.x = tex2D(vec2( kernelRadius, i)).g;
v2.y = tex2D(vec2( kernelRadius, -i)).g;
v2.z = tex2D(vec2(-kernelRadius, i)).g;
v2.w = tex2D(vec2(-kernelRadius, -i)).g;
v1 = max(v1, v2 );
v1.xy = max(v1.xy, v1.zw);
v1.x = max(v1.x, v1.y );
v1.x = max(v1.x, maxDist );
vec2 dist = getDistRect(v1.x, vec2(kernelRadius, i));
//minDist.z = min(minDist.z, sqlength(dist));
if (sqlength(dist) < minDist.z) {
maxDist = v1.x;
minDist = vec3(dist, sqlength(dist));
}
}
void main() {
if (kernelRadius <= 0) {
// initial stage; copy atlas-texture
fFragColor = texture(tex1, vTexCoord.st);
return;
}
if (kernelRadius == 10) {
// final stage; blur the texture
vec2
groundSurrounding = tex2D(vec2( 1.0, 1.0)).rb;
groundSurrounding += tex2D(vec2(-1.0, 1.0)).rb;
groundSurrounding += tex2D(vec2(-1.0, -1.0)).rb;
groundSurrounding += tex2D(vec2( 1.0, -1.0)).rb;
fFragColor = texture(tex1, vTexCoord.st);
if (groundSurrounding.x + fFragColor.r == 5.0) {
fFragColor.r = 1.0;
} else {
fFragColor.r = 0.93 - (groundSurrounding.y + fFragColor.b) / 5.0;
}
return;
}
if (kernelRadius == 9) {
// penultimate stage
vec2
blur = texture(tex0, vTexCoord.st + vec2( 1.0, 1.0) * texel0).rg;
blur += texture(tex0, vTexCoord.st + vec2(-1.0, 1.0) * texel0).rg;
blur += texture(tex0, vTexCoord.st + vec2(-1.0, -1.0) * texel0).rg;
blur += texture(tex0, vTexCoord.st + vec2( 1.0, -1.0) * texel0).rg;
fFragColor = texture(tex0, vTexCoord.st);
fFragColor.r = step(5.0, blur.x + fFragColor.r);
fFragColor.g = mix(fFragColor.g, blur.y * 0.25, 0.4);
return;
}
vec3 minDist = vec3(1e9);
// driver fails at unrolling when count is not known
// at compile-time, so we do it manually (radius is
// in [0.5, 8.5], so we need at most 8 iterations)
float iter = 0.0;
float maxValue = 0.0;
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
if (iter <= kernelRadius) { LoopIter(maxValue, minDist, iter); iter += 1.0; }
// PROCESS maxValue
//if (maxValue == 0.0)
// discard;
float fDist = 1.0 - (min(res, sqrt(minDist.z)) / res);
if (renderToAtlas) {
fFragColor = texture(tex0, vTexCoord.st);
} else {
fFragColor = texture(tex1, vTexCoord.st);
}
fFragColor.g = max(fFragColor.g, fDist * fDist * fDist);
}
|
