summaryrefslogtreecommitdiff
path: root/client/shaders/water_surface_shader/opengl_fragment.glsl
blob: 1aa721f831383bca47715f7f484162488df19b29 (plain)
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
166
167
168
169
170
171
172
173
uniform sampler2D baseTexture;
uniform sampler2D normalTexture;
uniform sampler2D textureFlags;

uniform vec4 skyBgColor;
uniform float fogDistance;
uniform vec3 eyePosition;

varying vec3 vPosition;
varying vec3 worldPosition;

varying vec3 eyeVec;
varying vec3 tsEyeVec;
varying vec3 lightVec;
varying vec3 tsLightVec;

bool normalTexturePresent = false;
bool texTileableHorizontal = false;
bool texTileableVertical = false;
bool texSeamless = false;

const float e = 2.718281828459;
const float BS = 10.0;

#ifdef ENABLE_TONE_MAPPING

/* Hable's UC2 Tone mapping parameters
	A = 0.22;
	B = 0.30;
	C = 0.10;
	D = 0.20;
	E = 0.01;
	F = 0.30;
	W = 11.2;
	equation used:  ((x * (A * x + C * B) + D * E) / (x * (A * x + B) + D * F)) - E / F
*/

vec3 uncharted2Tonemap(vec3 x)
{
	return ((x * (0.22 * x + 0.03) + 0.002) / (x * (0.22 * x + 0.3) + 0.06)) - 0.03334;
}

vec4 applyToneMapping(vec4 color)
{
	color = vec4(pow(color.rgb, vec3(2.2)), color.a);
	const float gamma = 1.6;
	const float exposureBias = 5.5;
	color.rgb = uncharted2Tonemap(exposureBias * color.rgb);
	// Precalculated white_scale from 
	//vec3 whiteScale = 1.0 / uncharted2Tonemap(vec3(W));
	vec3 whiteScale = vec3(1.036015346);
	color.rgb *= whiteScale;
	return vec4(pow(color.rgb, vec3(1.0 / gamma)), color.a);
}
#endif

void get_texture_flags()
{
	vec4 flags = texture2D(textureFlags, vec2(0.0, 0.0));
	if (flags.r > 0.5) {
		normalTexturePresent = true;
	}
	if (flags.g > 0.5) {
		texTileableHorizontal = true;
	}
	if (flags.b > 0.5) {
		texTileableVertical = true;
	}
	if (texTileableHorizontal && texTileableVertical) {
		texSeamless = true;
	}
}

float intensity(vec3 color)
{
	return (color.r + color.g + color.b) / 3.0;
}

float get_rgb_height(vec2 uv)
{
	return intensity(texture2D(baseTexture,uv).rgb);
}

vec4 get_normal_map(vec2 uv)
{
	vec4 bump = texture2D(normalTexture, uv).rgba;
	bump.xyz = normalize(bump.xyz * 2.0 -1.0);
	bump.y = -bump.y;
	return bump;
}

void main(void)
{
	vec3 color;
	vec4 bump;
	vec2 uv = gl_TexCoord[0].st;
	bool use_normalmap = false;
	get_texture_flags();

#ifdef ENABLE_PARALLAX_OCCLUSION
	if (normalTexturePresent) {
		vec3 tsEye = normalize(tsEyeVec);
		float height = PARALLAX_OCCLUSION_SCALE * texture2D(normalTexture, uv).a - PARALLAX_OCCLUSION_BIAS;
		uv = uv + texture2D(normalTexture, uv).z * height * vec2(tsEye.x,-tsEye.y);
	}
#endif

#ifdef USE_NORMALMAPS
	if (normalTexturePresent) {
		bump = get_normal_map(uv);
		use_normalmap = true;
	} 
#endif

	if (GENERATE_NORMALMAPS == 1 && use_normalmap == false) {
		float tl = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y+SAMPLE_STEP));
		float t  = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y-SAMPLE_STEP));
		float tr = get_rgb_height (vec2(uv.x+SAMPLE_STEP,uv.y+SAMPLE_STEP));
		float r  = get_rgb_height (vec2(uv.x+SAMPLE_STEP,uv.y));
		float br = get_rgb_height (vec2(uv.x+SAMPLE_STEP,uv.y-SAMPLE_STEP));
		float b  = get_rgb_height (vec2(uv.x,uv.y-SAMPLE_STEP));
		float bl = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y-SAMPLE_STEP));
		float l  = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y));
		float dX = (tr + 2.0 * r + br) - (tl + 2.0 * l + bl);
		float dY = (bl + 2.0 * b + br) - (tl + 2.0 * t + tr);
		bump = vec4 (normalize(vec3 (dX, -dY, NORMALMAPS_STRENGTH)),1.0);
		use_normalmap = true;
	}

vec4 base = texture2D(baseTexture, uv).rgba;

#ifdef ENABLE_BUMPMAPPING
	if (use_normalmap) {
		vec3 L = normalize(lightVec);
		vec3 E = normalize(eyeVec);
		float specular = pow(clamp(dot(reflect(L, bump.xyz), E), 0.0, 1.0),0.5);
		float diffuse = dot(E,bump.xyz);
		/* Mathematic optimization
		* Original: color = 0.05*base.rgb + diffuse*base.rgb + 0.2*specular*base.rgb;
		* This optimization save 2 multiplications (orig: 4 multiplications + 3 additions
		* end: 2 multiplications + 3 additions)
		*/
		color = (0.05 + diffuse + 0.2 * specular) * base.rgb;
	} else {
		color = base.rgb;
	}
#else
	color = base.rgb;
#endif

	vec4 col = vec4(color.rgb * gl_Color.rgb, 1.0); 

#if MATERIAL_TYPE == TILE_MATERIAL_LIQUID_TRANSPARENT || MATERIAL_TYPE == TILE_MATERIAL_LIQUID_OPAQUE
	float alpha = gl_Color.a;
	if (fogDistance != 0.0) {
		float d = max(0.0, min(length(eyeVec) / fogDistance * 1.5 - 0.6, 1.0));
		alpha = mix(alpha, 0.0, d);
	}
	col = vec4(col.rgb, alpha);
#else
	if (fogDistance != 0.0) {
		float d = max(0.0, min(length(eyeVec) / fogDistance * 1.5 - 0.6, 1.0));
		col = mix(col, skyBgColor, d);
	}
	col = vec4(col.rgb, base.a);
#endif

#ifdef ENABLE_TONE_MAPPING
	gl_FragColor = applyToneMapping(col);
#else
	gl_FragColor = col;
#endif
}