aboutsummaryrefslogtreecommitdiff
path: root/pugl/examples/demo_utils.h
blob: 6d3bb66fce1dae1f8e3de767103278d01b39d18b (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
/*
  Copyright 2012-2019 David Robillard <d@drobilla.net>

  Permission to use, copy, modify, and/or distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.

  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#ifndef PUGL_DEMO_UTILS_H
#define PUGL_DEMO_UTILS_H

#include "pugl/pugl.h"

#include <math.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

typedef struct {
	double lastReportTime;
} PuglFpsPrinter;

typedef float vec4[4];
typedef vec4  mat4[4];

// clang-format off

static const float cubeStripVertices[] = {
	-1.0f,  1.0f,  1.0f, // Front top left
	 1.0f,  1.0f,  1.0f, // Front top right
	-1.0f, -1.0f,  1.0f, // Front bottom left
	 1.0f, -1.0f,  1.0f, // Front bottom right
	 1.0f, -1.0f, -1.0f, // Back bottom right
	 1.0f,  1.0f,  1.0f, // Front top right
	 1.0f,  1.0f, -1.0f, // Back top right
	-1.0f,  1.0f,  1.0f, // Front top left
	-1.0f,  1.0f, -1.0f, // Back top left
	-1.0f, -1.0f,  1.0f, // Front bottom left
	-1.0f, -1.0f, -1.0f, // Back bottom left
	 1.0f, -1.0f, -1.0f, // Back bottom right
	-1.0f,  1.0f, -1.0f, // Back top left
	 1.0f,  1.0f, -1.0f  // Back top right
};

static const float cubeFrontLineLoop[] = {
	-1.0f,  1.0f,  1.0f, // Front top left
	 1.0f,  1.0f,  1.0f, // Front top right
	 1.0f, -1.0f,  1.0f, // Front bottom right
	-1.0f, -1.0f,  1.0f, // Front bottom left
};

static const float cubeBackLineLoop[] = {
	-1.0f,  1.0f, -1.0f, // Back top left
	 1.0f,  1.0f, -1.0f, // Back top right
	 1.0f, -1.0f, -1.0f, // Back bottom right
	-1.0f, -1.0f, -1.0f, // Back bottom left
};

static const float cubeSideLines[] = {
	-1.0f,  1.0f,  1.0f, // Front top left
	-1.0f,  1.0f, -1.0f, // Back top left

	-1.0f, -1.0f,  1.0f, // Front bottom left
	-1.0f, -1.0f, -1.0f, // Back bottom left

	 1.0f,  1.0f,  1.0f, // Front top right
	 1.0f,  1.0f, -1.0f, // Back top right

	 1.0f, -1.0f,  1.0f, // Front bottom right
	 1.0f, -1.0f, -1.0f, // Back bottom right
};

// clang-format on

static inline void
mat4Identity(mat4 m)
{
	for (int c = 0; c < 4; ++c) {
		for (int r = 0; r < 4; ++r) {
			m[c][r] = c == r ? 1.0f : 0.0f;
		}
	}
}

static inline void
mat4Translate(mat4 m, const float x, const float y, const float z)
{
	m[3][0] = x;
	m[3][1] = y;
	m[3][2] = z;
}

static inline void
mat4Mul(mat4 m, mat4 a, mat4 b)
{
	for (int c = 0; c < 4; ++c) {
		for (int r = 0; r < 4; ++r) {
			m[c][r] = 0.0f;
			for (int k = 0; k < 4; ++k) {
				m[c][r] += a[k][r] * b[c][k];
			}
		}
	}
}

static inline void
mat4Ortho(mat4        m,
          const float l,
          const float r,
          const float b,
          const float t,
          const float n,
          const float f)
{
	m[0][0] = 2.0f / (r - l);
	m[0][1] = m[0][2] = m[0][3] = 0.0f;

	m[1][1] = 2.0f / (t - b);
	m[1][0] = m[1][2] = m[1][3] = 0.0f;

	m[2][2] = -2.0f / (f - n);
	m[2][0] = m[2][1] = m[2][3] = 0.0f;

	m[3][0] = -(r + l) / (r - l);
	m[3][1] = -(t + b) / (t - b);
	m[3][2] = -(f + n) / (f - n);
	m[3][3] = 1.0f;
}

/// Calculate a projection matrix for a given perspective
static inline void
perspective(float* m, float fov, float aspect, float zNear, float zFar)
{
	const float h     = tanf(fov);
	const float w     = h / aspect;
	const float depth = zNear - zFar;
	const float q     = (zFar + zNear) / depth;
	const float qn    = 2 * zFar * zNear / depth;

	// clang-format off
	m[0]  = w;  m[1]  = 0;  m[2]  = 0;   m[3]  = 0;
	m[4]  = 0;  m[5]  = h;  m[6]  = 0;   m[7]  = 0;
	m[8]  = 0;  m[9]  = 0;  m[10] = q;   m[11] = -1;
	m[12] = 0;  m[13] = 0;  m[14] = qn;  m[15] = 0;
	// clang-format on
}

static inline void
puglPrintFps(const PuglWorld* world,
             PuglFpsPrinter*  printer,
             unsigned* const  framesDrawn)
{
	const double thisTime = puglGetTime(world);
	if (thisTime > printer->lastReportTime + 5) {
		const double fps = *framesDrawn / (thisTime - printer->lastReportTime);
		fprintf(stderr,
		        "%u frames in %.0f seconds = %.3f FPS\n",
		        *framesDrawn,
		        thisTime - printer->lastReportTime,
		        fps);

		printer->lastReportTime = thisTime;
		*framesDrawn            = 0;
	}
}

#endif // PUGL_DEMO_UTILS_H