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
|
#include <font.hpp>
FT_Library FontSystem::ftLibrary;
FT_Face FontSystem::ftFace;
std::string FontSystem::fontFamily;
std::map<int, std::vector<FT_Info>> FontSystem::fontData;
int FontSystem::currentSize = 0;
Color FontSystem::currentColor;
float FontSystem::currentZ = -8.0f;
void FontSystem::init(const std::string& ttf)
{
FT_Init_FreeType(&ftLibrary);
FT_New_Face(ftLibrary, ttf.c_str(), 0, &ftFace);
}
void FontSystem::setFontSize(int size)
{
auto result = fontData.try_emplace(size, 93);
if (result.second) {
FT_Set_Pixel_Sizes(ftFace, 0, size);
char c = 33;
for (auto& d : fontData.at(size)) {
glDeleteTextures(1, &d.tex);
glGenTextures(1, &d.tex); // Generate new texture name/locations?
// load the character from the font family file
FT_Load_Char(ftFace, c++, FT_LOAD_RENDER);
// transfer the character's bitmap (?) to a texture for rendering
glBindTexture(GL_TEXTURE_2D, d.tex);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S , GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T , GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER , GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER , GL_LINEAR);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
/**
* The just-created texture will render red-on-black if we don't do anything to it, so
* here we create a buffer 4 times the size and transform the texture into an RGBA array,
* making it white-on-black.
*/
auto& g = ftFace->glyph;
std::vector<uint32_t> buf (g->bitmap.width * g->bitmap.rows, 0xFFFFFFFF);
for (auto j = buf.size(); j--;)
buf[j] ^= !g->bitmap.buffer[j] ? buf[j] : 0;
d.wh.x = g->bitmap.width;
d.wh.y = g->bitmap.rows;
d.bl.x = g->bitmap_left;
d.bl.y = g->bitmap_top;
d.ad.x = g->advance.x >> 6;
d.ad.y = g->advance.y >> 6;
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, g->bitmap.width, g->bitmap.rows,
0, GL_RGBA, GL_UNSIGNED_BYTE, buf.data());
}
}
currentSize = size;
}
void FontSystem::setFontColor(float r, float g, float b)
{
currentColor.red = r;
currentColor.green = g;
currentColor.blue = b;
}
void FontSystem::setFontZ(float z)
{
currentZ = z;
}
vec2 FontSystem::putChar(float xx, float yy, char c)
{
const auto& ch = fontData.at(currentSize)[c - 33];
int x = xx, y = yy;
// get dimensions of the rendered character
vec2 c1 = {
static_cast<float>(floor(x) + ch.bl.x),
static_cast<float>(floor(y) + ch.bl.y)
};
const auto& c2 = ch.wh;
Render::textShader.use();
Render::textShader.enable();
// draw the character
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, ch.tex);
glUniform4f(Render::textShader.uniform[WU_tex_color], 1.0f, 1.0f, 1.0f, 1.0f);
GLfloat tex_coord[] = {
0.0, 1.0, // bottom left
1.0, 1.0, // bottom right
1.0, 0.0, // top right
1.0, 0.0, // top right
0.0, 0.0, // top left
0.0, 1.0, // bottom left
};
GLfloat text_vert[] = {
c1.x, c1.y - c2.y, currentZ, // bottom left
c1.x + c2.x, c1.y - c2.y, currentZ, // bottom right
c1.x + c2.x, c1.y + c2.y - c2.y, currentZ, // top right
c1.x + c2.x, c1.y + c2.y - c2.y, currentZ, // top right
c1.x, c1.y + c2.y - c2.y, currentZ, // top left
c1.x, c1.y - c2.y, currentZ // bottom left
};
glUniform4f(Render::textShader.uniform[WU_tex_color],
currentColor.red, currentColor.green, currentColor.blue, currentColor.alpha);
glVertexAttribPointer(Render::textShader.coord, 3, GL_FLOAT, GL_FALSE, 0, text_vert);
glVertexAttribPointer(Render::textShader.tex, 2, GL_FLOAT, GL_FALSE, 0, tex_coord);
glDrawArrays(GL_TRIANGLES, 0, 6);
glUniform4f(Render::textShader.uniform[WU_tex_color], 1.0, 1.0, 1.0, 1.0);
Render::textShader.disable();
Render::textShader.unuse();
// return the width.
return ch.ad;
}
|
