1 /*
2  * Copyright (c) 2007-2013 Scott Lembcke and Howling Moon Software
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a copy
5  * of this software and associated documentation files (the "Software"), to deal
6  * in the Software without restriction, including without limitation the rights
7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8  * copies of the Software, and to permit persons to whom the Software is
9  * furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20  * SOFTWARE.
21  */
22 module demo.Springies;
23 
24 import core.stdc.stdlib;
25 
26 import demo.dchip;
27 
28 import demo.ChipmunkDebugDraw;
29 import demo.ChipmunkDemo;
30 import demo.types;
31 
32 cpFloat springForce(cpConstraint* spring, cpFloat dist)
33 {
34     cpFloat clamp = 20.0f;
35     return cpfclamp(cpDampedSpringGetRestLength(spring) - dist, -clamp, clamp) * cpDampedSpringGetStiffness(spring);
36 }
37 
38 cpConstraint* new_spring(cpBody* a, cpBody* b, cpVect anchr1, cpVect anchr2, cpFloat restLength, cpFloat stiff, cpFloat damp)
39 {
40     cpConstraint* spring = cpDampedSpringNew(a, b, anchr1, anchr2, restLength, stiff, damp);
41     cpDampedSpringSetSpringForceFunc(spring, &springForce);
42 
43     return spring;
44 }
45 
46 void update(cpSpace* space, double dt)
47 {
48     cpSpaceStep(space, dt);
49 }
50 
51 cpBody* add_bar(cpSpace* space, cpVect a, cpVect b, int group)
52 {
53     cpVect  center = cpvmult(cpvadd(a, b), 1.0f / 2.0f);
54     cpFloat length = cpvlength(cpvsub(b, a));
55     cpFloat mass   = length / 160.0f;
56 
57     cpBody* body_ = cpSpaceAddBody(space, cpBodyNew(mass, mass * length * length / 12.0f));
58     cpBodySetPos(body_, center);
59 
60     cpShape* shape = cpSpaceAddShape(space, cpSegmentShapeNew(body_, cpvsub(a, center), cpvsub(b, center), 10.0f));
61     cpShapeSetGroup(shape, group);
62 
63     return body_;
64 }
65 
66 cpSpace* init()
67 {
68     cpSpace* space      = cpSpaceNew();
69     cpBody * staticBody = cpSpaceGetStaticBody(space);
70 
71     cpBody* body1  = add_bar(space, cpv(-240, 160), cpv(-160, 80), 1);
72     cpBody* body2  = add_bar(space, cpv(-160, 80), cpv(-80, 160), 1);
73     cpBody* body3  = add_bar(space, cpv(0, 160), cpv(80, 0), 0);
74     cpBody* body4  = add_bar(space, cpv(160, 160), cpv(240, 160), 0);
75     cpBody* body5  = add_bar(space, cpv(-240, 0), cpv(-160, -80), 2);
76     cpBody* body6  = add_bar(space, cpv(-160, -80), cpv(-80, 0), 2);
77     cpBody* body7  = add_bar(space, cpv(-80, 0), cpv(0, 0), 2);
78     cpBody* body8  = add_bar(space, cpv(0, -80), cpv(80, -80), 0);
79     cpBody* body9  = add_bar(space, cpv(240, 80), cpv(160, 0), 3);
80     cpBody* body10 = add_bar(space, cpv(160, 0), cpv(240, -80), 3);
81     cpBody* body11 = add_bar(space, cpv(-240, -80), cpv(-160, -160), 4);
82     cpBody* body12 = add_bar(space, cpv(-160, -160), cpv(-80, -160), 4);
83     cpBody* body13 = add_bar(space, cpv(0, -160), cpv(80, -160), 0);
84     cpBody* body14 = add_bar(space, cpv(160, -160), cpv(240, -160), 0);
85 
86     cpSpaceAddConstraint(space, cpPivotJointNew2(body1, body2, cpv(40, -40), cpv(-40, -40)));
87     cpSpaceAddConstraint(space, cpPivotJointNew2(body5, body6, cpv(40, -40), cpv(-40, -40)));
88     cpSpaceAddConstraint(space, cpPivotJointNew2(body6, body7, cpv(40, 40), cpv(-40, 0)));
89     cpSpaceAddConstraint(space, cpPivotJointNew2(body9, body10, cpv(-40, -40), cpv(-40, 40)));
90     cpSpaceAddConstraint(space, cpPivotJointNew2(body11, body12, cpv(40, -40), cpv(-40, 0)));
91 
92     cpFloat stiff = 100.0f;
93     cpFloat damp  = 0.5f;
94     cpSpaceAddConstraint(space, new_spring(staticBody, body1, cpv(-320, 240), cpv(-40, 40), 0.0f, stiff, damp));
95     cpSpaceAddConstraint(space, new_spring(staticBody, body1, cpv(-320, 80), cpv(-40, 40), 0.0f, stiff, damp));
96     cpSpaceAddConstraint(space, new_spring(staticBody, body1, cpv(-160, 240), cpv(-40, 40), 0.0f, stiff, damp));
97 
98     cpSpaceAddConstraint(space, new_spring(staticBody, body2, cpv(-160, 240), cpv(40, 40), 0.0f, stiff, damp));
99     cpSpaceAddConstraint(space, new_spring(staticBody, body2, cpv(0, 240), cpv(40, 40), 0.0f, stiff, damp));
100 
101     cpSpaceAddConstraint(space, new_spring(staticBody, body3, cpv(80, 240), cpv(-40, 80), 0.0f, stiff, damp));
102 
103     cpSpaceAddConstraint(space, new_spring(staticBody, body4, cpv(80, 240), cpv(-40, 0), 0.0f, stiff, damp));
104     cpSpaceAddConstraint(space, new_spring(staticBody, body4, cpv(320, 240), cpv(40, 0), 0.0f, stiff, damp));
105 
106     cpSpaceAddConstraint(space, new_spring(staticBody, body5, cpv(-320, 80), cpv(-40, 40), 0.0f, stiff, damp));
107 
108     cpSpaceAddConstraint(space, new_spring(staticBody, body9, cpv(320, 80), cpv(40, 40), 0.0f, stiff, damp));
109 
110     cpSpaceAddConstraint(space, new_spring(staticBody, body10, cpv(320, 0), cpv(40, -40), 0.0f, stiff, damp));
111     cpSpaceAddConstraint(space, new_spring(staticBody, body10, cpv(320, -160), cpv(40, -40), 0.0f, stiff, damp));
112 
113     cpSpaceAddConstraint(space, new_spring(staticBody, body11, cpv(-320, -160), cpv(-40, 40), 0.0f, stiff, damp));
114 
115     cpSpaceAddConstraint(space, new_spring(staticBody, body12, cpv(-240, -240), cpv(-40, 0), 0.0f, stiff, damp));
116     cpSpaceAddConstraint(space, new_spring(staticBody, body12, cpv(0, -240), cpv(40, 0), 0.0f, stiff, damp));
117 
118     cpSpaceAddConstraint(space, new_spring(staticBody, body13, cpv(0, -240), cpv(-40, 0), 0.0f, stiff, damp));
119     cpSpaceAddConstraint(space, new_spring(staticBody, body13, cpv(80, -240), cpv(40, 0), 0.0f, stiff, damp));
120 
121     cpSpaceAddConstraint(space, new_spring(staticBody, body14, cpv(80, -240), cpv(-40, 0), 0.0f, stiff, damp));
122     cpSpaceAddConstraint(space, new_spring(staticBody, body14, cpv(240, -240), cpv(40, 0), 0.0f, stiff, damp));
123     cpSpaceAddConstraint(space, new_spring(staticBody, body14, cpv(320, -160), cpv(40, 0), 0.0f, stiff, damp));
124 
125     cpSpaceAddConstraint(space, new_spring(body1, body5, cpv(40, -40), cpv(-40, 40), 0.0f, stiff, damp));
126     cpSpaceAddConstraint(space, new_spring(body1, body6, cpv(40, -40), cpv(40, 40), 0.0f, stiff, damp));
127     cpSpaceAddConstraint(space, new_spring(body2, body3, cpv(40, 40), cpv(-40, 80), 0.0f, stiff, damp));
128     cpSpaceAddConstraint(space, new_spring(body3, body4, cpv(-40, 80), cpv(-40, 0), 0.0f, stiff, damp));
129     cpSpaceAddConstraint(space, new_spring(body3, body4, cpv(40, -80), cpv(-40, 0), 0.0f, stiff, damp));
130     cpSpaceAddConstraint(space, new_spring(body3, body7, cpv(40, -80), cpv(40, 0), 0.0f, stiff, damp));
131     cpSpaceAddConstraint(space, new_spring(body3, body7, cpv(-40, 80), cpv(-40, 0), 0.0f, stiff, damp));
132     cpSpaceAddConstraint(space, new_spring(body3, body8, cpv(40, -80), cpv(40, 0), 0.0f, stiff, damp));
133     cpSpaceAddConstraint(space, new_spring(body3, body9, cpv(40, -80), cpv(-40, -40), 0.0f, stiff, damp));
134     cpSpaceAddConstraint(space, new_spring(body4, body9, cpv(40, 0), cpv(40, 40), 0.0f, stiff, damp));
135     cpSpaceAddConstraint(space, new_spring(body5, body11, cpv(-40, 40), cpv(-40, 40), 0.0f, stiff, damp));
136     cpSpaceAddConstraint(space, new_spring(body5, body11, cpv(40, -40), cpv(40, -40), 0.0f, stiff, damp));
137     cpSpaceAddConstraint(space, new_spring(body7, body8, cpv(40, 0), cpv(-40, 0), 0.0f, stiff, damp));
138     cpSpaceAddConstraint(space, new_spring(body8, body12, cpv(-40, 0), cpv(40, 0), 0.0f, stiff, damp));
139     cpSpaceAddConstraint(space, new_spring(body8, body13, cpv(-40, 0), cpv(-40, 0), 0.0f, stiff, damp));
140     cpSpaceAddConstraint(space, new_spring(body8, body13, cpv(40, 0), cpv(40, 0), 0.0f, stiff, damp));
141     cpSpaceAddConstraint(space, new_spring(body8, body14, cpv(40, 0), cpv(-40, 0), 0.0f, stiff, damp));
142     cpSpaceAddConstraint(space, new_spring(body10, body14, cpv(40, -40), cpv(-40, 0), 0.0f, stiff, damp));
143     cpSpaceAddConstraint(space, new_spring(body10, body14, cpv(40, -40), cpv(-40, 0), 0.0f, stiff, damp));
144 
145     return space;
146 }
147 
148 void destroy(cpSpace* space)
149 {
150     ChipmunkDemoFreeSpaceChildren(space);
151     cpSpaceFree(space);
152 }
153 
154 ChipmunkDemo Springies = {
155     "Springies",
156     1.0 / 60.0,
157     &init,
158     &update,
159     &ChipmunkDemoDefaultDrawImpl,
160     &destroy,
161 };