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
|
/*
* Copyright (C) 2020 - Vito Caputo - <vcaputo@pengaru.com>
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include "til.h"
#include "til_fb.h"
#include "puddle/puddle.h"
#define PUDDLE_SIZE 512
#define DRIZZLE_CNT 20
#define DEFAULT_VISCOSITY .01
typedef struct v3f_t {
float x, y, z;
} v3f_t;
typedef struct v2f_t {
float x, y;
} v2f_t;
typedef struct drizzle_setup_t {
til_setup_t til_setup;
float viscosity;
} drizzle_setup_t;
typedef struct drizzle_context_t {
puddle_t *puddle;
unsigned n_cpus;
drizzle_setup_t setup;
} drizzle_context_t;
static drizzle_setup_t drizzle_default_setup = {
.viscosity = DEFAULT_VISCOSITY,
};
/* convert a color into a packed, 32-bit rgb pixel value (taken from libs/ray/ray_color.h) */
static inline uint32_t color_to_uint32(v3f_t color) {
uint32_t pixel;
if (color.x > 1.0f) color.x = 1.0f;
if (color.y > 1.0f) color.y = 1.0f;
if (color.z > 1.0f) color.z = 1.0f;
if (color.x < .0f) color.x = .0f;
if (color.y < .0f) color.y = .0f;
if (color.z < .0f) color.z = .0f;
pixel = (uint32_t)(color.x * 255.0f);
pixel <<= 8;
pixel |= (uint32_t)(color.y * 255.0f);
pixel <<= 8;
pixel |= (uint32_t)(color.z * 255.0f);
return pixel;
}
static void * drizzle_create_context(unsigned ticks, unsigned num_cpus, til_setup_t *setup)
{
drizzle_context_t *ctxt;
if (!setup)
setup = &drizzle_default_setup.til_setup;
ctxt = calloc(1, sizeof(drizzle_context_t));
if (!ctxt)
return NULL;
ctxt->puddle = puddle_new(PUDDLE_SIZE, PUDDLE_SIZE);
if (!ctxt->puddle) {
free(ctxt);
return NULL;
}
ctxt->n_cpus = num_cpus;
ctxt->setup = *(drizzle_setup_t *)setup;
return ctxt;
}
static void drizzle_destroy_context(void *context)
{
drizzle_context_t *ctxt = context;
puddle_free(ctxt->puddle);
free(ctxt);
}
static int drizzle_fragmenter(void *context, const til_fb_fragment_t *fragment, unsigned number, til_fb_fragment_t *res_fragment)
{
drizzle_context_t *ctxt = context;
return til_fb_fragment_slice_single(fragment, ctxt->n_cpus, number, res_fragment);
}
static void drizzle_prepare_frame(void *context, unsigned ticks, unsigned n_cpus, til_fb_fragment_t *fragment, til_fragmenter_t *res_fragmenter)
{
drizzle_context_t *ctxt = context;
*res_fragmenter = drizzle_fragmenter;
for (int i = 0; i < DRIZZLE_CNT; i++) {
int x = rand() % (PUDDLE_SIZE - 1);
int y = rand() % (PUDDLE_SIZE - 1);
/* TODO: puddle should probably offer a normalized way of setting an
* area to a value, so if PUDDLE_SIZE changes this automatically
* would adapt to cover the same portion of the unit square...
*/
puddle_set(ctxt->puddle, x, y, 1.f);
puddle_set(ctxt->puddle, x + 1, y, 1.f);
puddle_set(ctxt->puddle, x, y + 1, 1.f);
puddle_set(ctxt->puddle, x + 1, y + 1, 1.f);
}
puddle_tick(ctxt->puddle, ctxt->setup.viscosity);
}
static void drizzle_render_fragment(void *context, unsigned ticks, unsigned cpu, til_fb_fragment_t *fragment)
{
drizzle_context_t *ctxt = context;
float xf = 1.f / (float)fragment->frame_width;
float yf = 1.f / (float)fragment->frame_height;
v2f_t coord;
coord.y = yf * (float)fragment->y;
for (int y = fragment->y; y < fragment->y + fragment->height; y++) {
coord.x = xf * (float)fragment->x;
for (int x = fragment->x; x < fragment->x + fragment->width; x++) {
v3f_t color = {};
uint32_t pixel;
color.z = puddle_sample(ctxt->puddle, &coord);
pixel = color_to_uint32(color);
til_fb_fragment_put_pixel_unchecked(fragment, x, y, pixel);
coord.x += xf;
}
coord.y += yf;
}
}
static int drizzle_setup(const til_settings_t *settings, til_setting_t **res_setting, const til_setting_desc_t **res_desc, til_setup_t **res_setup)
{
const char *viscosity;
const char *values[] = {
".005",
".01",
".03",
".05",
NULL
};
int r;
r = til_settings_get_and_describe_value(settings,
&(til_setting_desc_t){
.name = "Puddle viscosity",
.key = "viscosity",
.regex = "\\.[0-9]+",
.preferred = TIL_SETTINGS_STR(DEFAULT_VISCOSITY),
.values = values,
.annotations = NULL
},
&viscosity,
res_setting,
res_desc);
if (r)
return r;
if (res_setup) {
drizzle_setup_t *setup;
setup = til_setup_new(sizeof(*setup), (void(*)(til_setup_t *))free);
if (!setup)
return -ENOMEM;
sscanf(viscosity, "%f", &setup->viscosity);
*res_setup = &setup->til_setup;
}
return 0;
}
til_module_t drizzle_module = {
.create_context = drizzle_create_context,
.destroy_context = drizzle_destroy_context,
.prepare_frame = drizzle_prepare_frame,
.render_fragment = drizzle_render_fragment,
.name = "drizzle",
.description = "Classic 2D rain effect (threaded (poorly))",
.author = "Vito Caputo <vcaputo@pengaru.com>",
.setup = drizzle_setup,
};
|
