summaryrefslogtreecommitdiff
path: root/drivers/gles3/shaders/particles.glsl
blob: 56e5545efe32c555d3528669366b3adff7fb5736 (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
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
[vertex]

layout(location = 0) in highp vec4 color;
layout(location = 1) in highp vec4 velocity_active;
layout(location = 2) in highp vec4 custom;
layout(location = 3) in highp vec4 xform_1;
layout(location = 4) in highp vec4 xform_2;
layout(location = 5) in highp vec4 xform_3;

struct Attractor {

	vec3 pos;
	vec3 dir;
	float radius;
	float eat_radius;
	float strength;
	float attenuation;
};

#define MAX_ATTRACTORS 64

uniform bool emitting;
uniform float system_phase;
uniform float prev_system_phase;
uniform int total_particles;
uniform float explosiveness;
uniform float randomness;
uniform float time;
uniform float delta;

uniform int attractor_count;
uniform Attractor attractors[MAX_ATTRACTORS];
uniform bool clear;
uniform uint cycle;
uniform float lifetime;
uniform mat4 emission_transform;
uniform uint random_seed;

out highp vec4 out_color; //tfb:
out highp vec4 out_velocity_active; //tfb:
out highp vec4 out_custom; //tfb:
out highp vec4 out_xform_1; //tfb:
out highp vec4 out_xform_2; //tfb:
out highp vec4 out_xform_3; //tfb:

#if defined(USE_MATERIAL)

layout(std140) uniform UniformData { //ubo:0

MATERIAL_UNIFORMS

};

#endif

VERTEX_SHADER_GLOBALS

uint hash(uint x) {

	x = ((x >> uint(16)) ^ x) * uint(0x45d9f3b);
	x = ((x >> uint(16)) ^ x) * uint(0x45d9f3b);
	x = (x >> uint(16)) ^ x;
	return x;
}

void main() {

#ifdef PARTICLES_COPY

	out_color = color;
	out_velocity_active = velocity_active;
	out_custom = custom;
	out_xform_1 = xform_1;
	out_xform_2 = xform_2;
	out_xform_3 = xform_3;

#else

	bool apply_forces = true;
	bool apply_velocity = true;
	float local_delta = delta;

	float mass = 1.0;

	float restart_phase = float(gl_VertexID) / float(total_particles);

	if (randomness > 0.0) {
		uint seed = cycle;
		if (restart_phase >= system_phase) {
			seed -= uint(1);
		}
		seed *= uint(total_particles);
		seed += uint(gl_VertexID);
		float random = float(hash(seed) % uint(65536)) / 65536.0;
		restart_phase += randomness * random * 1.0 / float(total_particles);
	}

	restart_phase *= (1.0 - explosiveness);
	bool restart = false;
	bool shader_active = velocity_active.a > 0.5;

	if (system_phase > prev_system_phase) {
		// restart_phase >= prev_system_phase is used so particles emit in the first frame they are processed

		if (restart_phase >= prev_system_phase && restart_phase < system_phase) {
			restart = true;
#ifdef USE_FRACTIONAL_DELTA
			local_delta = (system_phase - restart_phase) * lifetime;
#endif
		}

	} else if (delta > 0.0) {
		if (restart_phase >= prev_system_phase) {
			restart = true;
#ifdef USE_FRACTIONAL_DELTA
			local_delta = (1.0 - restart_phase + system_phase) * lifetime;
#endif
		} else if (restart_phase < system_phase) {
			restart = true;
#ifdef USE_FRACTIONAL_DELTA
			local_delta = (system_phase - restart_phase) * lifetime;
#endif
		}
	}

	uint current_cycle = cycle;

	if (system_phase < restart_phase) {
		current_cycle -= uint(1);
	}

	uint particle_number = current_cycle * uint(total_particles) + uint(gl_VertexID);
	int index = int(gl_VertexID);

	if (restart) {
		shader_active = emitting;
	}

	mat4 xform;

#if defined(ENABLE_KEEP_DATA)
	if (clear) {
#else
	if (clear || restart) {
#endif
		out_color = vec4(1.0);
		out_velocity_active = vec4(0.0);
		out_custom = vec4(0.0);
		if (!restart)
			shader_active = false;

		xform = mat4(
				vec4(1.0, 0.0, 0.0, 0.0),
				vec4(0.0, 1.0, 0.0, 0.0),
				vec4(0.0, 0.0, 1.0, 0.0),
				vec4(0.0, 0.0, 0.0, 1.0));
	} else {
		out_color = color;
		out_velocity_active = velocity_active;
		out_custom = custom;
		xform = transpose(mat4(xform_1, xform_2, xform_3, vec4(vec3(0.0), 1.0)));
	}

	if (shader_active) {
		//execute shader

		{
VERTEX_SHADER_CODE
		}

#if !defined(DISABLE_FORCE)

		if (false) {

			vec3 force = vec3(0.0);
			for (int i = 0; i < attractor_count; i++) {

				vec3 rel_vec = xform[3].xyz - attractors[i].pos;
				float dist = length(rel_vec);
				if (attractors[i].radius < dist)
					continue;
				if (attractors[i].eat_radius > 0.0 && attractors[i].eat_radius > dist) {
					out_velocity_active.a = 0.0;
				}

				rel_vec = normalize(rel_vec);

				float attenuation = pow(dist / attractors[i].radius, attractors[i].attenuation);

				if (attractors[i].dir == vec3(0.0)) {
					//towards center
					force += attractors[i].strength * rel_vec * attenuation * mass;
				} else {
					force += attractors[i].strength * attractors[i].dir * attenuation * mass;
				}
			}

			out_velocity_active.xyz += force * local_delta;
		}
#endif

#if !defined(DISABLE_VELOCITY)

		if (true) {

			xform[3].xyz += out_velocity_active.xyz * local_delta;
		}
#endif
	} else {
		xform = mat4(0.0);
	}

	xform = transpose(xform);

	out_velocity_active.a = mix(0.0, 1.0, shader_active);

	out_xform_1 = xform[0];
	out_xform_2 = xform[1];
	out_xform_3 = xform[2];

#endif //PARTICLES_COPY
}

[fragment]

// any code here is never executed, stuff is filled just so it works

#if defined(USE_MATERIAL)

layout(std140) uniform UniformData {

MATERIAL_UNIFORMS

};

#endif

FRAGMENT_SHADER_GLOBALS

void main() {

	{
LIGHT_SHADER_CODE
	}

	{
FRAGMENT_SHADER_CODE
	}
}