samples.Plink source code

1 
2 // written in the D programming language
3 
4 module samples.Plink;
5 
6 import dchip.all;
7 
8 import samples.ChipmunkDemo;
9 
10 import std.math;
11 
12 static cpSpace *space;
13 
14 // Iterate over all of the bodies and reset the ones that have fallen offscreen.
15 static void
16 eachBody(cpBody *_body, void *unused)
17 {
18     if(_body.p.y < -260 || cpfabs(_body.p.x) > 340){
19         cpFloat x = frand()*640 - 320;
20         _body.p = cpv(x, 260);
21     }
22 }
23 
24 static void
25 update(int ticks)
26 {
27     int steps = 1;
28     cpFloat dt = 1.0f/60.0f/cast(cpFloat)steps;
29 
30     for(int i=0; i<steps; i++){
31         cpSpaceStep(space, dt);
32         cpSpaceEachBody(space, &eachBody, null);
33     }
34 }
35 
36 enum NUM_VERTS = 5;
37 
38 static cpSpace *
39 init()
40 {
41     cpResetShapeIdCounter();
42 
43     space = cpSpaceNew();
44     space.iterations = 5;
45     space.gravity = cpv(0, -100);
46 
47     cpBody *_body;
48     cpBody *staticBody = space.staticBody;
49     cpShape *shape;
50 
51     // Create vertexes for a pentagon shape.
52     cpVect verts[NUM_VERTS];
53     for(int i=0; i<NUM_VERTS; i++){
54         cpFloat angle = -2.0f*PI*i/(cast(cpFloat) NUM_VERTS);
55         verts[i] = cpv(10.0f*cos(angle), 10.0f*sin(angle));
56     }
57 
58     // Vertexes for a triangle shape.
59     //port: ?
60     enum cpVect tris[] = [
61         cpv(-15,-15),
62         cpv(  0, 10),
63         cpv( 15,-15),
64     ];
65 
66     // Create the static triangles.
67     foreach(i; 0..9){
68         foreach(j; 0..6){
69             cpFloat stagger = (j%2)*40;
70             cpVect offset;
71             offset.x = (i*80) - 320 + stagger;
72             offset.y = (j*70) - 240;
73 
74             shape = cpSpaceAddShape(space, cpPolyShapeNew(staticBody, 3, tris.ptr, offset));
75             shape.e = 1.0f; shape.u = 1.0f;
76             shape.layers = NOT_GRABABLE_MASK;
77         }
78     }
79 
80     // Add lots of pentagons.
81     for(int i=0; i<300; i++){
82         _body = cpSpaceAddBody(space, cpBodyNew(1.0f, cpMomentForPoly(1.0f, NUM_VERTS, verts.ptr, cpvzero)));
83         cpFloat x = frand()*640 - 320;
84         _body.p = cpv(x, 350);
85 
86         shape = cpSpaceAddShape(space, cpPolyShapeNew(_body, NUM_VERTS, verts.ptr, cpvzero));
87         shape.e = 0.0f; shape.u = 0.4f;
88     }
89 
90     return space;
91 }
92 
93 static void
94 destroy()
95 {
96     ChipmunkDemoFreeSpaceChildren(space);
97     cpSpaceFree(space);
98 }
99 
100 chipmunkDemo Plink = {
101     "Plink",
102     null,
103     &init,
104     &update,
105     &destroy,
106 };