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
|
#include "../modules.h"
#if JIN_MODULES_RENDER
#include "font.h"
#include <stdio.h>
#define STB_TRUETYPE_IMPLEMENTATION
#include "3rdparty/stb/stb_truetype.h"
#include "color.h"
namespace jin
{
namespace render
{
using namespace jin::math;
const int BITMAP_WIDTH = 512;
const int BITMAP_HEIGHT = 512;
const int PIXEL_HEIGHT = 32;
Font::Font():Drawable()
{
}
// ttf file read buffer
static unsigned char ttf_buffer[1 << 20];
// bitmap for saving font data
static unsigned char temp_bitmap[BITMAP_WIDTH * BITMAP_HEIGHT];
void Font::loadf(const char* path)
{
fread(ttf_buffer, 1, 1 << 20, fopen(path, "rb"));
loadb(ttf_buffer);
}
/**
* load from memory
*/
void Font::loadb(const unsigned char* data)
{
stbtt_BakeFontBitmap(data, 0, PIXEL_HEIGHT, temp_bitmap, BITMAP_WIDTH, BITMAP_HEIGHT, 32, 96, cdata);
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, BITMAP_WIDTH,
BITMAP_HEIGHT, 0, GL_ALPHA, GL_UNSIGNED_BYTE, temp_bitmap);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glBindTexture(GL_TEXTURE_2D, 0);
}
/**
* get texture quad
*/
static Quad getCharQuad(const stbtt_bakedchar* chardata, int pw, int ph, int char_index)
{
float ipw = 1.0f / pw, iph = 1.0f / ph;
const stbtt_bakedchar *b = chardata + char_index;
Quad q;
q.x = b->x0 * ipw;
q.y = b->y0 * iph;
q.w = b->x1 * ipw - b->x0 * ipw;
q.h = b->y1 * iph - b->y0 * iph;
return q;
}
/**
* render function draw mutiple times
* in loop
*/
void Font::render(
const char* text, // rendered text
float x, float y, // render position
int fheight, // font height
int spacing, // font spacing
int lheight) // line height
{
float _x = x,
_y = y;
int len = strlen(text);
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, texture);
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
// for saving clip quad
stbtt_aligned_quad q;
// render every given character
int xc = x;
int yc = y;
float factor = fheight / (float)PIXEL_HEIGHT;
for (int i = 0; i < len; ++i)
{
char c = text[i];
if (c == '\n')
{
xc = x;
yc += lheight;
continue;
}
// only support ASCII
Quad q = getCharQuad(cdata, 512, 512, c - 32);
float s0 = q.x,
s1 = q.x + q.w,
t0 = q.y,
t1 = q.y + q.h;
// texture quad
float tc[] = {
s0, t1,
s1, t1,
s1, t0,
s0, t0
};
// character bound box
stbtt_bakedchar box = cdata[c - 32];
float width = factor * (box.x1 - box.x0);
float height = factor * (box.y1 - box.y0);
float xoffset = factor * box.xoff;
// I don't know why add PIXEL_HEIGHT to box.yoff, but
// it works.
float yoffset = factor * (box.yoff + PIXEL_HEIGHT);
float xadvance = factor * box.xadvance;
// render quad
float vc[] = {
xc + xoffset, yc + height + yoffset,
xc + width + xoffset, yc + height + yoffset,
xc + width + xoffset, yc + yoffset,
xc + xoffset, yc + yoffset
};
// forward to next character
xc += xadvance + spacing;
glTexCoordPointer(2, GL_FLOAT, 0, tc);
glVertexPointer(2, GL_FLOAT, 0, vc);
glDrawArrays(GL_QUADS, 0, 4);
}
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glDisableClientState(GL_VERTEX_ARRAY);
glBindTexture(GL_TEXTURE_2D, 0);
glDisable(GL_TEXTURE_2D);
}
void Font::box(const char* str, int fheight, int spacing, int lheight, int* w, int * h)
{
int len = strlen(str);
float xc = 0;
int yc = len ? lheight: 0;
int maxX = 0;
float factor = fheight / (float)PIXEL_HEIGHT;
for (int i = 0; i < len; ++i)
{
char c = str[i];
if (c == '\n')
{
yc += lheight;
xc = 0;
continue;
}
stbtt_bakedchar box = cdata[c - 32];
xc += factor * box.xadvance + spacing;
if (xc > maxX) maxX = xc;
}
*w = maxX;
*h = yc;
}
}
}
#endif // JIN_MODULES_RENDER
|
