Opengl touch events
This is a much more complicated example which mashes some of the previous examples together, I have written it as an example but also to test out shaders and different pipelines to get better opengl performance.
Hopefully this example will help you get started writing awesome touch based apps with gtk, if anything is unclear let me know in the comments below.
OpenGL in a drawing areaTouch screen events1 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 |
#!/usr/bin/env python
import sys
import time
import random
import pprint
import Xlib
from Xlib.display import Display
from gi.repository import Gtk, Gdk, GdkX11, GLib, GObject
from ctypes import *
from numpy import array
from OpenGL.GL import *
from OpenGL.GL import shaders
from OpenGL.GLU import gluPerspective, gluLookAt
from OpenGL.arrays import vbo
from OpenGL import GLX
try:
from OpenGL.GLX import struct__XDisplay
except ImportError as err:
from OpenGL.raw._GLX import struct__XDisplay
from OpenGL.GL import GL_VERTEX_SHADER, GL_FRAGMENT_SHADER
from OpenGL.GL import shaders, glGetUniformLocation
from helper import shader
from helper import cube as createcube
class gtkgl:
""" these method do not seem to exist in python x11 library lets exploit the c methods
useful link http://www.opengl.org/wiki/Programming_OpenGL_in_Linux:_GLX_and_Xlib"""
xlib = cdll.LoadLibrary('libX11.so')
xlib.XOpenDisplay.argtypes = [c_char_p]
xlib.XOpenDisplay.restype = POINTER(struct__XDisplay)
xdisplay = xlib.XOpenDisplay(None)
display = Xlib.display.Display()
attrs = []
xwindow_id = None
width = height = 500
def __init__(self):
""" lets setup are opengl settings and create the context for our window """
self.add_attribute(GLX.GLX_RGBA, True)
self.add_attribute(GLX.GLX_RED_SIZE, 8)
self.add_attribute(GLX.GLX_GREEN_SIZE, 8)
self.add_attribute(GLX.GLX_BLUE_SIZE, 8)
self.add_attribute(GLX.GLX_DOUBLEBUFFER, 1)
self.add_attribute(GLX.GLX_DEPTH_SIZE, 24)
xvinfo = GLX.glXChooseVisual(self.xdisplay, self.display.get_default_screen(), self.get_attributes())
print("run glxinfo to match this visual id %s " % hex(xvinfo.contents.visualid))
self.context = GLX.glXCreateContext(self.xdisplay, xvinfo, None, True)
def add_attribute(self, setting, value):
"""just to nicely add opengl parameters"""
self.attrs.append(setting)
self.attrs.append(value)
def get_attributes(self):
""" return our parameters in the expected structure"""
attrs = self.attrs + [0, 0]
return (c_int * len(attrs))(*attrs)
def configure(self, wid):
""" """
self.xwindow_id = GdkX11.X11Window.get_xid(wid)
if(not GLX.glXMakeCurrent(self.xdisplay, self.xwindow_id, self.context)):
print ('failed configuring context')
glViewport(0, 0, self.width, self.height)
def draw_start(self):
"""make cairo context current for drawing"""
if(not GLX.glXMakeCurrent(self.xdisplay, self.xwindow_id, self.context)):
print ("failed to get the context for drawing")
def draw_finish(self):
"""swap buffer when we have finished drawing"""
GLX.glXSwapBuffers(self.xdisplay, self.xwindow_id)
class scene:
width, height = 600, 600
rotationx = 0.0
rotationy = 0.0
rotation_incx = 0.5
rotation_incy = 0.5
radius = 0
touch_count = 0
touch_previous = 0, 0
touch_start_one = 0, 0
touch_start_two = 0, 0
touch_end_one = 0, 0
touch_end_two = 0, 0
touch_time = 0
camera_distance = 25
cube_length = 1.0
cube_size = cube_length / 2
def __init__(self):
"""setup everything in the correct order"""
self.glwrap = gtkgl()
self.setup_opengl()
self.generate()
self.gui()
self.mode = 'vbo all cubes'
def gui(self):
"""load in the gui and connect the events and set our properties"""
self.start_time = time.time()
self.frame = 1
xml = Gtk.Builder()
xml.add_from_file('gui.glade')
self.window = xml.get_object('window1')
self.mode_widget = xml.get_object('cmbmode')
self.mode_widget.connect('changed', self.change_mode)
self.rotate_widget = xml.get_object('spinrotate')
self.rotate_widget.connect('value-changed', self.change_rotate_speed)
self.radius_widget = xml.get_object('spinradius')
self.radius_widget.connect('value-changed', self.change_radius)
self.color_widget = xml.get_object('btncolor')
self.color_widget.connect('clicked', self.change_color)
self.canvas_widget = xml.get_object('canvas')
self.canvas_widget.connect('configure_event', self.on_configure_event)
self.canvas_widget.connect('draw', self.on_draw)
self.canvas_widget.set_double_buffered(False)
self.canvas_widget.set_size_request(self.glwrap.width, self.glwrap.height)
self.canvas_widget.add_events(Gdk.EventMask.TOUCH_MASK)
self.canvas_widget.connect('touch-event', self.touched)
self.window.show_all()
GObject.idle_add(self.loop_draw)
def touched(self, widget, ev):
"""basic touch support, count the touches so we no how many fingers
basic pinc zoom along the x, single finger slide to rotate"""
if ev.get_source_device().get_source() == Gdk.InputSource.TOUCHSCREEN:
if ev.touch.type == Gdk.EventType.TOUCH_BEGIN:
self.touch_start = ev.touch.x, ev.touch.y
self.touch_count += 1
if self.touch_count == 2:
self.touch_start_two = ev.touch.x, ev.touch.y
self.touch_previous = ev.touch.x, ev.touch.y
if ev.touch.type == Gdk.EventType.TOUCH_UPDATE:
if ev.touch.time - self.touch_time < 100:
return True
if self.touch_count == 2:
#basic pinch zoom along the x axis
d1 = self.touch_previous[0] - ev.touch.x
if d1 > 1:
self.camera_distance += self.camera_distance * 0.05
self.touch_previous = ev.touch.x, ev.touch.y
if d1 < 1:
self.camera_distance -= self.camera_distance * 0.05
self.touch_previous = ev.touch.x, ev.touch.y
self.update_camera()
self.touch_time = ev.touch.time
if ev.touch.type == Gdk.EventType.TOUCH_END:
self.touch_end = ev.touch.x, ev.touch.y
#set rotation when touch ends
if self.touch_count == 1:
self.rotation_incx = (self.touch_start[0] - self.touch_end[0]) * 0.01
self.rotation_incy = (self.touch_start[1] - self.touch_end[1]) * 0.01
self.touch_count = 0
def in_circle(self, center_x, center_y, center_z, radius, x, y, z):
""" test if our cordinate lies inside our sphere"""
square_dist = (center_x - x) ** 2 + (center_y - y) ** 2 + (center_z - z) ** 2
return square_dist <= radius ** 2
def change_color(self, widget):
#regenerate the scene
self.generate()
def change_mode(self, widget):
#change whats drawn and how
self.mode = widget.get_active_text().lower()
print(widget.get_active_text())
def change_rotate_speed(self, widget):
#handle spinner rotation speed event
self.rotation_incx = widget.get_value()
self.rotation_incy = widget.get_value()
def change_radius(self, widget):
#increase size of circle and number of polygons
self.radius = int(widget.get_value())
self.generate()
def loop_draw(self):
#send redraw event to drawing area widget
self.canvas_widget.queue_draw()
return True
def on_configure_event(self, widget, event):
"""if we recieve a configure event for example a resize, then grab the context settings and resize our scene """
self.glwrap.width = widget.get_allocation().width
self.glwrap.height = widget.get_allocation().height
self.width, self.height = self.glwrap.width, self.glwrap.height
#update our states because we have reconfigured the display
self.glwrap.configure(widget.get_window())
self.glwrap.draw_start()
self.update_camera()
self.setup_shaders()
glEnable(GL_DEPTH_TEST)
glDepthMask(GL_TRUE)
glDepthFunc(GL_LEQUAL)
glDepthRange(0.0, 1.0)
glEnable(GL_CULL_FACE)
glCullFace(GL_BACK)
glFrontFace(GL_CW)
self.glwrap.draw_finish()
return True
def on_draw(self, widget, context):
"""if we recieve a draw event redraw our opengl scene"""
self.elapsed_time = time.time() - self.start_time
self.frame += 1
if self.elapsed_time > 1:
print('fps %d' % self.frame)
self.start_time = time.time()
self.frame = 1
self.glwrap.draw_start()
self.draw()
self.glwrap.draw_finish()
def generate(self):
self.cubes = []
#position cubes inside a sphere radius
for shift_x in range(-self.radius, self.radius + 1):
for shift_y in range(-self.radius, self.radius + 1):
for shift_z in range(-self.radius, self.radius + 1):
x = shift_x * self.cube_length
y = shift_y * self.cube_length
z = shift_z * self.cube_length
if not self.in_circle(0, 0, 0, self.radius, x, y, z):
continue
#random colours / textures if we want
color = random.choice([0.85, 0.15]), random.choice([0.85, 0.15]), random.choice([0.85, 0.15])
self.cubes.append(createcube((x, y, z), color, self.cube_size))
self.test_cube = createcube((x, y, z), (random.choice([0.85, 0.15]), random.choice([0.85, 0.15]), random.choice([0.85, 0.15])), 6)
faces = []
for cube in self.cubes:
faces += cube.get_data()
print('Generated %s Cubes' % str(len(self.cubes)))
print('Generated %s Tringles' % str(len(faces) / 3))
self.vbuffer = vbo.VBO(array(faces, 'f'))
def setup_shaders(self):
self.shader_program = shader()
self.shader_program.compile()
def setup_opengl(self):
glShadeModel(GL_SMOOTH)
glClearColor(0.0, 0.0, 0.0, 0.0)
glClearDepth(1.0)
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST)
glPolygonMode(GL_FRONT, GL_FILL)
def update_camera(self):
glViewport(0, 0, self.width, self.height)
glMatrixMode(GL_PROJECTION)
glLoadIdentity()
gluPerspective(45, 1.0 * self.width / self.height, 1.0, 80.0)
gluLookAt(self.camera_distance, self.camera_distance, self.camera_distance, # location
0.0, 0.0, 0.0, # lookat
0.0, 1.0, 0.0) # up direction
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
def draw_test(self):
#lets do a simple rotation so we can see the objects are 3d
glRotatef(self.rotationx, 1.0, 0.0, 0.0)
self.rotationx += self.rotation_incx
glRotatef(self.rotationy, 0.0, 1.0, 0.0)
self.rotationy += self.rotation_incy
#use our shader program and enable vertex loading
glUseProgram(self.shader_program.program)
glEnableClientState(GL_VERTEX_ARRAY)
glEnableClientState(GL_COLOR_ARRAY)
#render the triangles into a virtual buffer object
self.test_cube.bind()
glVertexPointer(3, GL_FLOAT, 24, self.test_cube.vbuffer)
glColorPointer(3, GL_FLOAT, 24, self.test_cube.vbuffer + 12)
glDrawArrays(GL_TRIANGLES, 0, self.test_cube.vbuffer_size)
self.test_cube.unbind()
#restore opengl to our previous state
glDisableClientState(GL_COLOR_ARRAY)
glDisableClientState(GL_VERTEX_ARRAY)
shaders.glUseProgram(0)
def draw_vbo_per_cube(self):
#lets do a simple rotation so we can see the objects are 3d
glRotatef(self.rotationx, 1.0, 0.0, 0.0)
self.rotationx += self.rotation_incx
glRotatef(self.rotationy, 0.0, 1.0, 0.0)
self.rotationy += self.rotation_incy
# use our shader program and enable vertex loading
glUseProgram(self.shader_program.program)
glEnableClientState(GL_VERTEX_ARRAY)
glEnableClientState(GL_COLOR_ARRAY)
# render the triangles into a virtual buffer object
for shape in self.cubes:
shape.bind()
glVertexPointer(3, GL_FLOAT, 24, shape.vbuffer)
glColorPointer(3, GL_FLOAT, 24, shape.vbuffer + 12)
glDrawArrays(GL_TRIANGLES, 0, shape.vbuffer_size)
shape.unbind()
#restore opengl to our previous state
glDisableClientState(GL_COLOR_ARRAY)
glDisableClientState(GL_VERTEX_ARRAY)
shaders.glUseProgram(0)
def draw_vbo_all_cubes(self):
#lets do a simple rotation so we can see the objects are 3d
glRotatef(self.rotationx, 1.0, 0.0, 0.0)
self.rotationx += self.rotation_incx
glRotatef(self.rotationy, 0.0, 1.0, 0.0)
self.rotationy += self.rotation_incy
# use our shader program and enable vertex loading
glUseProgram(self.shader_program.program)
glEnableClientState(GL_VERTEX_ARRAY)
glEnableClientState(GL_COLOR_ARRAY)
# render the triangles into a virtual buffer object
self.vbuffer.bind()
glVertexPointer(3, GL_FLOAT, 24, self.vbuffer)
glColorPointer(3, GL_FLOAT, 24, self.vbuffer + 12)
glDrawArrays(GL_TRIANGLES, 0, len(self.vbuffer))
self.vbuffer.unbind()
#restore opengl to our previous state
glDisableClientState(GL_COLOR_ARRAY)
glDisableClientState(GL_VERTEX_ARRAY)
shaders.glUseProgram(0)
def draw(self):
glEnable(GL_DEPTH_TEST)
glClearDepth(1.0)
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
glLoadIdentity()
if self.mode == 'vbo test cube':
self.draw_test()
if self.mode == 'vbo per cube':
self.draw_vbo_per_cube()
if self.mode == 'vbo all cubes':
self.draw_vbo_all_cubes()
if __name__ == '__main__':
glexample = scene()
GLib.threads_init()
Gdk.threads_init()
Gdk.threads_enter()
Gtk.main()
Gdk.threads_leave()
|
The file below is a simple helper to reduce the size of the files, it contains the shader and a point and cube class used in the main program above.
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 |
import numpy
from numpy import array
from OpenGL.GL import *
from OpenGL.GL import shaders
from OpenGL.arrays import vbo
from OpenGL._bytes import bytes, _NULL_8_BYTE
def compileShader( source, shaderType ):
"""Compile shader source of given type
source -- GLSL source-code for the shader
shaderType -- GLenum GL_VERTEX_SHADER, GL_FRAGMENT_SHADER, etc,
returns GLuint compiled shader reference
raises RuntimeError when a compilation failure occurs
"""
if isinstance(source, str):
source = [source]
elif isinstance(source, bytes):
source = [source.decode('utf-8')]
shader = glCreateShader(shaderType)
glShaderSource(shader, source)
glCompileShader(shader)
result = glGetShaderiv(shader, GL_COMPILE_STATUS)
if not(result):
# TODO: this will be wrong if the user has
# disabled traditional unpacking array support.
raise RuntimeError(
"""Shader compile failure (%s): %s"""%(
result,
glGetShaderInfoLog( shader ),
),
source,
shaderType,
)
return shader
class shader:
vertex = """#version 120
//attributes in values
attribute vec3 inPosition;
attribute vec3 inColor;
//varying sending to fragment shader
varying vec4 outColor;
void main(){
vec4 fragmentPos = gl_ModelViewMatrix * gl_Vertex;
gl_Position = (gl_ProjectionMatrix * fragmentPos);
outColor = vec4(gl_Color.rgb, 1);
}"""
fragment = """#version 120
varying vec4 outColor;
void main(){
gl_FragColor = outColor;
}"""
program = None
def compile(self):
self.program = shaders.compileProgram(
compileShader(self.vertex, GL_VERTEX_SHADER),
compileShader(self.fragment, GL_FRAGMENT_SHADER),)
class point:
__slots__ = ['x', 'y', 'z', 'xyz', 'vertex']
def __init__(self, p, c=(1, 0, 0)):
""" Position in 3d space as a tuple or list, and colour in tuple or list format"""
self.x, self.y, self.z = p
self.vertex = array([self.x, self.y, self.z, c[0], c[1], c[2]], 'f')
class cube:
def __init__(self, p1, color, size=0.5):
self.color = array([1, 0, 0], 'f')
#self.xyz = p1
self.points = (
point((p1[0] - size, p1[1] + size, p1[2] - size), (color)),
point((p1[0] - size, p1[1] + size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] + size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] + size, p1[2] - size), (color)),
point((p1[0] - size, p1[1] - size, p1[2] - size), (color)),
point((p1[0] - size, p1[1] - size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] - size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] - size, p1[2] - size), (color)),
)
self.vbuffer = vbo.VBO(array(self.get_data(), 'f'))
self.vbuffer_size = len(self.get_data())
def bind(self):
self.vbuffer.bind()
def unbind(self):
self.vbuffer.unbind()
def get_data(self):
return (
self.points[0].vertex, self.points[2].vertex, self.points[1].vertex,
self.points[0].vertex, self.points[3].vertex, self.points[2].vertex,
self.points[0].vertex, self.points[1].vertex, self.points[5].vertex,
self.points[0].vertex, self.points[5].vertex, self.points[4].vertex,
self.points[0].vertex, self.points[7].vertex, self.points[3].vertex,
self.points[0].vertex, self.points[4].vertex, self.points[7].vertex,
self.points[6].vertex, self.points[2].vertex, self.points[3].vertex,
self.points[6].vertex, self.points[3].vertex, self.points[7].vertex,
self.points[6].vertex, self.points[1].vertex, self.points[2].vertex,
self.points[6].vertex, self.points[5].vertex, self.points[1].vertex,
self.points[6].vertex, self.points[4].vertex, self.points[5].vertex,
self.points[6].vertex, self.points[7].vertex, self.points[4].vertex,
)
class cube:
def __init__(self, p1, color, size=0.5):
self.color = array([1, 0, 0], 'f')
#self.xyz = p1
self.points = (
point((p1[0] - size, p1[1] + size, p1[2] - size), (color)),
point((p1[0] - size, p1[1] + size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] + size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] + size, p1[2] - size), (color)),
point((p1[0] - size, p1[1] - size, p1[2] - size), (color)),
point((p1[0] - size, p1[1] - size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] - size, p1[2] + size), (color)),
point((p1[0] + size, p1[1] - size, p1[2] - size), (color)),
)
self.vbuffer = vbo.VBO(array(self.get_data(), 'f'))
self.vbuffer_size = len(self.get_data())
def bind(self):
self.vbuffer.bind()
def unbind(self):
self.vbuffer.unbind()
def get_data(self):
return (
self.points[0].vertex, self.points[2].vertex, self.points[1].vertex,
self.points[0].vertex, self.points[3].vertex, self.points[2].vertex,
self.points[0].vertex, self.points[1].vertex, self.points[5].vertex,
self.points[0].vertex, self.points[5].vertex, self.points[4].vertex,
self.points[0].vertex, self.points[7].vertex, self.points[3].vertex,
self.points[0].vertex, self.points[4].vertex, self.points[7].vertex,
self.points[6].vertex, self.points[2].vertex, self.points[3].vertex,
self.points[6].vertex, self.points[3].vertex, self.points[7].vertex,
self.points[6].vertex, self.points[1].vertex, self.points[2].vertex,
self.points[6].vertex, self.points[5].vertex, self.points[1].vertex,
self.points[6].vertex, self.points[4].vertex, self.points[5].vertex,
self.points[6].vertex, self.points[7].vertex, self.points[4].vertex,
)
|