samples.UnsafeOps source code

1 
2 // written in the D programming language
3 
4 module samples.UnsafeOps;
5 
6 import dchip.all;
7 
8 import samples.ChipmunkDemo;
9 
10 import gameApp;
11 
12 import std.math;
13 
14 static cpSpace *space;
15 
16 enum M_PI = PI;
17 enum M_PI_2 = PI*0.5f;
18 
19 enum NUM_CIRCLES = 30;
20 
21 static cpShape *circles[NUM_CIRCLES];
22 static cpFloat circleRadius = 30.0f;
23 
24 static void
25 update(int ticks)
26 {
27     if(arrowDirection.y){
28         circleRadius = cpfmax(10.0f, circleRadius + arrowDirection.y);
29 
30         for(int i=0; i<NUM_CIRCLES; i++){
31             circles[i].body_.m = cpMomentForCircle(1.0f, 0.0f, circleRadius, cpvzero);
32             cpCircleShapeSetRadius(circles[i], circleRadius);
33         }
34     }
35 
36     int steps = 1;
37     cpFloat dt = 1.0f/60.0f/cast(cpFloat)steps;
38 
39     for(int i=0; i<steps; i++){
40         cpSpaceStep(space, dt);
41     }
42 }
43 
44 static cpSpace *
45 init()
46 {
47     cpResetShapeIdCounter();
48 
49     space = cpSpaceNew();
50     space.iterations = 5;
51     space.gravity = cpv(0, -100);
52 
53     cpBody *body_, staticBody = space.staticBody;
54     cpShape *shape;
55 
56     shape = cpSpaceAddStaticShape(space, cpSegmentShapeNew(staticBody, cpv(-320,-240), cpv(-320,240), 0.0f));
57     shape.e = 1.0f; shape.u = 1.0f;
58     shape.layers = NOT_GRABABLE_MASK;
59 
60     shape = cpSpaceAddStaticShape(space, cpSegmentShapeNew(staticBody, cpv(320,-240), cpv(320,240), 0.0f));
61     shape.e = 1.0f; shape.u = 1.0f;
62     shape.layers = NOT_GRABABLE_MASK;
63 
64     shape = cpSpaceAddStaticShape(space, cpSegmentShapeNew(staticBody, cpv(-320,-240), cpv(320,-240), 0.0f));
65     shape.e = 1.0f; shape.u = 1.0f;
66     shape.layers = NOT_GRABABLE_MASK;
67 
68     for(int i=0; i<NUM_CIRCLES; i++){
69         body_ = cpSpaceAddBody(space, cpBodyNew(1.0f, cpMomentForCircle(1.0f, 0.0f, circleRadius, cpvzero)));
70         body_.p = cpvmult(cpv(frand()*2.0f - 1.0f, frand()*2.0f - 1.0f), circleRadius*5.0f);
71 
72         circles[i] = shape = cpSpaceAddShape(space, cpCircleShapeNew(body_, circleRadius, cpvzero));
73         shape.e = 0.0f; shape.u = 1.0f;
74     }
75 
76     //strcat(messageString,
77     //	"chipmunk_unsafe.h Contains functions for changing shapes, but they can cause severe stability problems if used incorrectly.\n"
78     //	"Shape changes occur as instantaneous changes to position without an accompanying velocity change. USE WITH CAUTION!");
79     return space;
80 }
81 
82 static void
83 destroy()
84 {
85     ChipmunkDemoFreeSpaceChildren(space);
86     cpSpaceFree(space);
87 }
88 
89 chipmunkDemo UnsafeOps = {
90     "Unsafe Operations",
91     null,
92     &init,
93     &update,
94     &destroy,
95 };