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
|
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# -----------------------------------------------------------------------------
#
# FreeType high-level python API - Copyright 2011 Nicolas P. Rougier
# Distributed under the terms of the new BSD license.
#
# -----------------------------------------------------------------------------
'''
Subpixel rendering AND positioning using OpenGL and shaders.
'''
import numpy as np
import OpenGL.GL as gl
import OpenGL.GLUT as glut
from texture_font import TextureFont, TextureAtlas
from shader import Shader
vert='''
uniform sampler2D texture;
uniform vec2 pixel;
attribute float modulo;
varying float m;
void main() {
gl_FrontColor = gl_Color;
gl_TexCoord[0].xy = gl_MultiTexCoord0.xy;
gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
m = modulo;
}
'''
frag='''
uniform sampler2D texture;
uniform vec2 pixel;
varying float m;
void main() {
float gamma = 1.0;
vec2 uv = gl_TexCoord[0].xy;
vec4 current = texture2D(texture, uv);
vec4 previous= texture2D(texture, uv+vec2(-1,0)*pixel);
current = pow(current, vec4(1.0/gamma));
previous = pow(previous, vec4(1.0/gamma));
float r = current.r;
float g = current.g;
float b = current.b;
float a = current.a;
if( m <= 0.333 )
{
float z = m/0.333;
r = mix(current.r, previous.b, z);
g = mix(current.g, current.r, z);
b = mix(current.b, current.g, z);
}
else if( m <= 0.666 )
{
float z = (m-0.33)/0.333;
r = mix(previous.b, previous.g, z);
g = mix(current.r, previous.b, z);
b = mix(current.g, current.r, z);
}
else if( m < 1.0 )
{
float z = (m-0.66)/0.334;
r = mix(previous.g, previous.r, z);
g = mix(previous.b, previous.g, z);
b = mix(current.r, previous.b, z);
}
float t = max(max(r,g),b);
vec4 color = vec4(0.,0.,0., (r+g+b)/2.);
color = t*color + (1.-t)*vec4(r,g,b, min(min(r,g),b));
gl_FragColor = vec4( color.rgb, color.a);
}
'''
class Label:
def __init__(self, text, font, color=(1.0, 1.0, 1.0, 0.0), x=0, y=0,
width=None, height=None, anchor_x='left', anchor_y='baseline'):
self.text = text
self.vertices = np.zeros((len(text)*4,3), dtype=np.float32)
self.indices = np.zeros((len(text)*6, ), dtype=np.uint)
self.colors = np.zeros((len(text)*4,4), dtype=np.float32)
self.texcoords= np.zeros((len(text)*4,2), dtype=np.float32)
self.attrib = np.zeros((len(text)*4,1), dtype=np.float32)
pen = [x,y]
prev = None
for i,charcode in enumerate(text):
glyph = font[charcode]
kerning = glyph.get_kerning(prev)
x0 = pen[0] + glyph.offset[0] + kerning
dx = x0-int(x0)
x0 = int(x0)
y0 = pen[1] + glyph.offset[1]
x1 = x0 + glyph.size[0]
y1 = y0 - glyph.size[1]
u0 = glyph.texcoords[0]
v0 = glyph.texcoords[1]
u1 = glyph.texcoords[2]
v1 = glyph.texcoords[3]
index = i*4
indices = [index, index+1, index+2, index, index+2, index+3]
vertices = [[x0,y0,1],[x0,y1,1],[x1,y1,1], [x1,y0,1]]
texcoords = [[u0,v0],[u0,v1],[u1,v1], [u1,v0]]
colors = [color,]*4
self.vertices[i*4:i*4+4] = vertices
self.indices[i*6:i*6+6] = indices
self.texcoords[i*4:i*4+4] = texcoords
self.colors[i*4:i*4+4] = colors
self.attrib[i*4:i*4+4] = dx
pen[0] = pen[0]+glyph.advance[0]/64.0 + kerning
pen[1] = pen[1]+glyph.advance[1]/64.0
prev = charcode
width = pen[0]-glyph.advance[0]/64.0+glyph.size[0]
if anchor_y == 'top':
dy = -round(font.ascender)
elif anchor_y == 'center':
dy = +round(-font.height/2-font.descender)
elif anchor_y == 'bottom':
dy = -round(font.descender)
else:
dy = 0
if anchor_x == 'right':
dx = -width/1.0
elif anchor_x == 'center':
dx = -width/2.0
else:
dx = 0
self.vertices += (round(dx), round(dy), 0)
def draw(self):
gl.glEnable( gl.GL_TEXTURE_2D )
gl.glDisable( gl.GL_DEPTH_TEST )
gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
gl.glEnableClientState(gl.GL_COLOR_ARRAY)
gl.glEnableClientState(gl.GL_TEXTURE_COORD_ARRAY)
gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
gl.glVertexPointer(3, gl.GL_FLOAT, 0, self.vertices)
gl.glColorPointer(4, gl.GL_FLOAT, 0, self.colors)
gl.glTexCoordPointer(2, gl.GL_FLOAT, 0, self.texcoords)
r,g,b = 0,0,0
gl.glColor( 1, 1, 1, 1 )
gl.glEnable( gl.GL_BLEND )
#gl.glBlendFunc( gl.GL_CONSTANT_COLOR_EXT, gl.GL_ONE_MINUS_SRC_COLOR )
#gl.glBlendColor(r,g,b,1)
gl.glBlendFunc( gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA )
gl.glBlendColor( 1, 1, 1, 1 )
gl.glEnableVertexAttribArray( 1 );
gl.glVertexAttribPointer( 1, 1, gl.GL_FLOAT, gl.GL_FALSE, 0, self.attrib)
shader.bind()
shader.uniformi('texture', 0)
shader.uniformf('pixel', 1.0/512, 1.0/512)
gl.glDrawElements(gl.GL_TRIANGLES, len(self.indices),
gl.GL_UNSIGNED_INT, self.indices)
shader.unbind()
gl.glDisableVertexAttribArray( 1 );
gl.glDisableClientState(gl.GL_VERTEX_ARRAY)
gl.glDisableClientState(gl.GL_COLOR_ARRAY)
gl.glDisableClientState(gl.GL_TEXTURE_COORD_ARRAY)
gl.glDisable( gl.GL_TEXTURE_2D )
gl.glDisable( gl.GL_BLEND )
if __name__ == '__main__':
import sys
atlas = TextureAtlas(512,512,3)
def on_display( ):
#gl.glClearColor(0,0,0,1)
gl.glClearColor(1,1,1,1)
gl.glClear(gl.GL_COLOR_BUFFER_BIT | gl.GL_DEPTH_BUFFER_BIT)
gl.glBindTexture( gl.GL_TEXTURE_2D, atlas.texid )
for label in labels:
label.draw()
gl.glColor(0,0,0,1)
gl.glBegin(gl.GL_LINES)
gl.glVertex2i(15,0)
gl.glVertex2i(15, 330)
gl.glVertex2i(225, 0)
gl.glVertex2i(225, 330)
gl.glEnd()
glut.glutSwapBuffers( )
def on_reshape( width, height ):
gl.glViewport( 0, 0, width, height )
gl.glMatrixMode( gl.GL_PROJECTION )
gl.glLoadIdentity( )
gl.glOrtho( 0, width, 0, height, -1, 1 )
gl.glMatrixMode( gl.GL_MODELVIEW )
gl.glLoadIdentity( )
def on_keyboard( key, x, y ):
if key == '\033':
sys.exit( )
glut.glutInit( sys.argv )
glut.glutInitDisplayMode( glut.GLUT_DOUBLE | glut.GLUT_RGBA | glut.GLUT_DEPTH )
glut.glutCreateWindow( "Freetype OpenGL" )
glut.glutReshapeWindow( 240, 330 )
glut.glutDisplayFunc( on_display )
glut.glutReshapeFunc( on_reshape )
glut.glutKeyboardFunc( on_keyboard )
font = TextureFont(atlas, './Arial.ttf', 9)
text = "|... A Quick Brown Fox Jumps Over The Lazy Dog"
labels = []
x,y = 20,310
for i in range(30):
labels.append(Label(text=text, font=font, x=x, y=y))
x += 0.1000000000001
y -= 10
atlas.upload()
shader = Shader(vert,frag)
glut.glutMainLoop( )
|
