Sharedwww / talks / 2006-05-09-sage-digipen / tutorial / basic-5.pyOpen in CoCalc
Author: William A. Stein
1# Soya 3D tutorial
2# Copyright (C) 2004 Jean-Baptiste LAMY
3#
4# This program is free software; you can redistribute it and/or modify
6# the Free Software Foundation; either version 2 of the License, or
7# (at your option) any later version.
8#
9# This program is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12# GNU General Public License for more details.
13#
14# You should have received a copy of the GNU General Public License
15# along with this program; if not, write to the Free Software
16# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
17
18
19# basic-5: Event management : a keyboard-controlled caterpillar
20
21# In this lesson, our caterpillar will obey you !
22# You'll learn how to use SDL events with Soya.
23# Use the cursor arrows to control the caterpillar.
24
25
26# Import the Soya module.
27# The soya.sdlconst module contains all the SDL constants.
28
29import sys, os, os.path, soya, soya.sdlconst
30
31soya.init()
32soya.path.append(os.path.join(os.path.dirname(sys.argv[0]), "data"))
33
34# Creates a scene.
35
36scene = soya.World()
37
38
39# The CaterpillarHead class is very similar to the CaterpillarHead class of the previous
40# lesson.
41
43  def __init__(self, parent):
45    self.speed                  = soya.Vector(self, 0.0, 0.0, 0.0)
46    self.rotation_lateral_speed = 0.0
47
48  def begin_round(self):
49    soya.Volume.begin_round(self)
50
51    # Loops over all Soya / SDL events.
52    # Each event is a tuple ; the first value indicates the event type and the other
53    # values depend on the type. The following event types exist :
54    #  - (KEYDOWN, keysym, modifier) where keysym is the key's code (a K_* constant)
55    #    and modifier is a flag combining some of the MOD_* constant (to test the presence
56    #    of a modifier, do e.g. for left shift: modifier & soya.sdlconst.MOD_LSHIFT).
57    #  - (KEYUP, keysym, modifier)
58    #  - (MOUSEMOTION, x, y, xrel, yrel) where x and y are the mouse coordinates (in
59    #    pixel) ; xrel and yrel are the relative mouse coordinates (the difference since
60    #    next mouse motion event).
61    #  - (MOUSEBUTTONDOWN, button, x, y) where button is the mouse button number and
62    #    x and y are the mouse coordinates. Mouse buttons are :
63    #    - 1 : left
64    #    - 2 : middle
65    #    - 3 : right
66    #    - 4 : roll up
67    #    - 5 : roll down
68    #  - (MOUSEBUTTONUP, button, x, y)
69    #  - (JOYAXISMOTION, axis, value) XXX
70    #  - (JOYBUTTONDOWN, button) XXX
71    #  - (VIDEORESIZE, new_width, new_height)
72
73    for event in soya.process_event():
74
75      # Checks for key down (press) events.
76
77      if event[0] == soya.sdlconst.KEYDOWN:
78
79        # The up and down arrows set the caterpillar speed to a negative or positive value.
80
81        if   event[1] == soya.sdlconst.K_UP:     self.speed.z = -0.2
82        elif event[1] == soya.sdlconst.K_DOWN:   self.speed.z =  0.1
83
84        # The left and right arrow modify the rotation speed.
85
86        elif event[1] == soya.sdlconst.K_LEFT:   self.rotation_lateral_speed =  10.0
87        elif event[1] == soya.sdlconst.K_RIGHT:  self.rotation_lateral_speed = -10.0
88
89        # Pressing the escape or 'q' key will exit the idler mainloop, and thus terminate
90        # the program. soya.IDLER.stop() is the right way to end your application, and
91        # causes the Idler.idle() method to return.
92
93        elif event[1] == soya.sdlconst.K_q:      soya.IDLER.stop()
94        elif event[1] == soya.sdlconst.K_ESCAPE: soya.IDLER.stop()
95
96      # Checks for key up (release) events.
97
98      elif event[0] == soya.sdlconst.KEYUP:
99
100        # When up or down arrows are released, the speed is set to zero.
101
102        if   event[1] == soya.sdlconst.K_UP:     self.speed.z = 0.0
103        elif event[1] == soya.sdlconst.K_DOWN:   self.speed.z = 0.0
104
105        # When left or right arrows are released, the rotation speed is set to zero.
106
107        elif event[1] == soya.sdlconst.K_LEFT:   self.rotation_lateral_speed = 0.0
108        elif event[1] == soya.sdlconst.K_RIGHT:  self.rotation_lateral_speed = 0.0
109
110      elif event[0] == soya.sdlconst.QUIT:
111        soya.IDLER.stop()
112
113    # Do the rotation
114
115    self.rotate_lateral(self.rotation_lateral_speed)
116
120
121
122# CaterpillarPiece hasn't changed since the previous tutorial.
123
124class CaterpillarPiece(soya.Volume):
125  def __init__(self, parent, previous):
126    soya.Volume.__init__(self, parent, soya.Shape.get("caterpillar"))
127    self.previous = previous
128    self.speed = soya.Vector(self, 0.0, 0.0, -0.2)
129
130  def begin_round(self):
131    soya.Volume.begin_round(self)
132    self.look_at(self.previous)
133    if self.distance_to(self.previous) < 1.5: self.speed.z =  0.0
134    else:                                     self.speed.z = -0.2
135
139
140
141# Creates a caterpillar head and 10 caterpillar piece of body.
142
145
147for i in range(10):
148  previous_caterpillar_piece = CaterpillarPiece(scene, previous_caterpillar_piece)
149  previous_caterpillar_piece.x = i + 1
150
151# Creates a light.
152
153light = soya.Light(scene)
154light.set_xyz(2.0, 5.0, 0.0)
155
156# Creates a camera.
157
158camera = soya.Camera(scene)
159camera.set_xyz(0.0, 15.0, 15.0)