I am trying to make a simple pyglet app (with Python 3.7) where I can draw a grid, some tiles, color them etc. While also being able to pan, zoom around, so I followed this question :
How to pan and zoom properly in 2D?
However the on_resize() event of the MyWindow subclass
seems to be called repeatedly after run() is called, even if I don't touch the window, and the script crashes with a max recursion depth, except when I comment out its self.width = width and self.height = height lines.
But then resizing the window squishes the objects I'm drawing...
I would like resizing to just show more of the map, keeping the aspect ratio and size of drawn objects.
I have added some print() calls to check what happens, but I'm truly at a loss with what's happening here.
import pyglet
from pyglet.gl import *
from algorithm.priorityqueue import PriorityQueue
from algorithm.squaregrid import heuristic, SquareGrid
ZOOM_IN_FACTOR = 1.2
ZOOM_OUT_FACTOR = 1/ZOOM_IN_FACTOR
class Triangle:
def __init__(self, color):
self.color = color
self.vertices = pyglet.graphics.vertex_list(3, ('v3f', [0,0,0, 1000,0,0, 1000,1000,0]),
('c4B', self.color*3))
def draw(self, x, y, z):
glTranslatef(x, y, z)
self.vertices.draw(GL_TRIANGLES)
glTranslatef(-x, -y, -z)
class Tile:
def __init__(self, size, color):
self.size = size
self.color = color
self.vertices = pyglet.graphics.vertex_list(
4, ('v3f', [0,0,0, 0+self.size,0,0,
0+self.size,0+self.size,0, 0,0+self.size,0]),
('c4B', self.color*4))
def draw(self, x, y, z):
glTranslatef(x, y, z)
self.vertices.draw(GL_QUADS)
glTranslatef(-x, -y, -z)
class Line:
def __init__(self, start, end, color, stroke):
self.color = color
self.stroke = stroke
self.sx, self.sy = start
self.ex, self.ey = end
self.vertices = pyglet.graphics.vertex_list(
2, ('v3f', [self.sx,self.sy,0, self.ex,self.ey,0]),
('c4B', self.color*2))
def draw(self):
glLineWidth(self.stroke)
self.vertices.draw(GL_LINES)
class MyWindow(pyglet.window.Window):
def __init__(self, width, height, *args, **kwargs):
conf = Config(sample_buffers=1,
samples=4,
depth_size=16,
double_buffer=True)
super().__init__(width, height, config=conf, *args, **kwargs)
#self.set_minimum_size(960, 540)
#glClearColor(0.8, 0.8, 0.8, 1.0)
#glOrtho(0, self.width, 0, self.height, -10, 10) # setup orthogonal projection
self.left = 0
self.right = width
self.bottom = 0
self.top = height
self.zoom_level = 1
self.zoomed_width = width
self.zoomed_height = height
print("init finished")
def init_gl(self, width, height):
print("init_gl started")
# Clear color
glClearColor(255/255, 255/255, 255/255, 255/255)
# Antialiasing
glEnable(GL_LINE_SMOOTH)
glEnable(GL_POLYGON_SMOOTH)
glHint(GL_LINE_SMOOTH_HINT, GL_NICEST)
# Alpha Blending
glEnable(GL_BLEND)
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
# Viewport
glViewport(0, 0, width, height)
def drawstuff(self):
print("drawstuff called")
self.triangle = Triangle((255, 0, 0, 255))
self.square = Tile(10, (255,0,255,255))
self.gridlines = []
for j in range(0,25):
self.gridlines.append(Line((0, 40*j),(1000, 40*j),(50,50,50,255), 2))
for i in range(0,25):
self.gridlines.append(Line((40*i, 0),(40*i, 1000),(50,50,50,255), 2))
def on_resize(self, width, height):
print("on_resize called")
# It crashes here!
self.width = width
print(width)
self.height = height
print(height)
self.init_gl(width, height)
def on_mouse_drag(self, x, y, dx, dy, buttons, modifiers):
# Move camera
self.left -= dx*self.zoom_level
self.right -= dx*self.zoom_level
self.bottom -= dy*self.zoom_level
self.top -= dy*self.zoom_level
def on_mouse_scroll(self, x, y, dx, dy):
# Scale factor
f = ZOOM_IN_FACTOR if dy<0 else ZOOM_OUT_FACTOR if dy>0 else 1
# If in proper range
if .2 < self.zoom_level*f < 5:
self.zoom_level *= f
print(self.width, self.height)
mouse_x = x/self.width
mouse_y = y/self.height
mouse_x_in_world = self.left + mouse_x * self.zoomed_width
mouse_y_in_world = self.bottom + mouse_y * self.zoomed_height
self.zoomed_width *= f
self.zoomed_height *= f
self.left = mouse_x_in_world - mouse_x * self.zoomed_width
self.right = mouse_x_in_world + (1 - mouse_x) * self.zoomed_width
self.bottom = mouse_y_in_world - mouse_y * self.zoomed_height
self.top = mouse_y_in_world + (1 - mouse_y) * self.zoomed_height
def on_draw(self):
print("draw called")
# Init projection matrix
glMatrixMode(GL_PROJECTION)
glLoadIdentity()
# Init Modelview matrix
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
# Save default modelview matrix
glPushMatrix()
# Clear window with ClearColor
glClear(GL_COLOR_BUFFER_BIT)
# Set Orthographic projection matrix
glOrtho(self.left, self.right, self.bottom, self.top, 1, -1)
#self.draw_background()
self.triangle.draw(0, 0, 0)
self.square.draw(-100, -100, 0)
for line in self.gridlines:
line.draw()
# Remove default modelview matrix
glPopMatrix()
def run(self):
print("run called")
pyglet.app.run()
print("run finished")
if __name__ == "__main__":
App = MyWindow(800, 500, resizable=True)
App.drawstuff()
App.run()
And the console shows :
$ python3 environments/testapp.py
init finished
drawstuff called
run called
on_resize called
on_resize called
on_resize called
on_resize called
on_resize called
etc. with at some point :
on_resize called
on_resize called
Traceback (most recent call last):
File "environments/testapp.py", line 185, in <module>
App.run()
File "environments/testapp.py", line 177, in run
pyglet.app.run()
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/app/__init__.py", line 107, in run
event_loop.run()
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/app/base.py", line 159, in run
self._legacy_setup()
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/app/base.py", line 182, in _legacy_setup
window.dispatch_pending_events()
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/xlib/__init__.py", line 914, in dispatch_pending_events
EventDispatcher.dispatch_event(self, *self._event_queue.pop(0))
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/event.py", line 415, in dispatch_event
if getattr(self, event_type)(*args):
File "environments/testapp.py", line 110, in on_resize
self.width = width
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/__init__.py", line 964, in width
self.set_size(new_width, self.height)
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/xlib/__init__.py", line 574, in set_size
self.dispatch_event('on_resize', width, height)
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/__init__.py", line 1323, in dispatch_event
if EventDispatcher.dispatch_event(self, *args) != False:
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/event.py", line 415, in dispatch_event
if getattr(self, event_type)(*args):
File "environments/testapp.py", line 110, in on_resize
self.width = width
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/__init__.py", line 964, in width
self.set_size(new_width, self.height)
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/xlib/__init__.py", line 574, in set_size
self.dispatch_event('on_resize', width, height)
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/window/__init__.py", line 1323, in dispatch_event
if EventDispatcher.dispatch_event(self, *args) != False:
With the last 10 lines repeating for a while, and at the end :
if EventDispatcher.dispatch_event(self, *args) != False:
File "/home/admin/.local/lib/python3.7/site-packages/pyglet/event.py", line 415, in dispatch_event
if getattr(self, event_type)(*args):
File "environments/testapp.py", line 108, in on_resize
print("on_resize called")
RecursionError: maximum recursion depth exceeded while calling a Python object
I find it weird that run() is calling on_resize() on its own, and I really have no clue as to why reassigning the attributes self.width and self.height is entering a recursion.
It also crashes when the value assigned is not width or height, but any constant number as well, and also whether the Window instance is passed resizable = True or = False as argument
run does not call on_resize(), but run executes the event loop and the resize event occurs once after initializing the window.
pyglet.window provides the properties .width and .height, thus there is no need to set them by self.width = width respectively self.height = height. Likely, assigning a value to self.width or self.height triggers the on_resize event. If you do that in on_resize, that causes an endless recursion.
That self.width and self.height contain the current size of the window, can be verified with ease, by printing the values in on_resize:
class MyWindow(pyglet.window.Window):
# [...]
def on_resize(self, width, height):
print("on_resize called")
print(self.width, width)
print(self.height, height)
Do not assign a value to self.width or self.height, if the new value is equal the current value:
class MyWindow(pyglet.window.Window):
# [...]
def on_resize(self, width, height):
new_width = ...
new_height = ...
if new_width != width:
self.width = new_width
if new_height != height:
self.height = new_height