1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
#include "CollisionDetector.h"
#include "../../../base/ScopeTimer.h"
#include "../../../wrapper/WrapHelper.h"
namespace avg {
CollisionDetector::CollisionDetector(const Bitmap& bmpA, const Bitmap& bmpB)
{
m_pBmpA = new Bitmap(bmpA.getSize(), B8G8R8A8);
m_pBmpA->copyPixels(bmpA);
m_pBmpB = new Bitmap(bmpB.getSize(), B8G8R8A8);
m_pBmpB->copyPixels(bmpB);
}
CollisionDetector::~CollisionDetector()
{
delete m_pBmpA;
delete m_pBmpB;
}
static ProfilingZoneID CollisionDetectorProfilingZone("Detect collisions");
bool CollisionDetector::detect(glm::vec2 posA, glm::vec2 posB)
{
ScopeTimer Timer(CollisionDetectorProfilingZone);
int widthA = m_pBmpA->getSize().x;
int heightA = m_pBmpA->getSize().y;
int rightA = posA.x + widthA;
int bottomA = posA.y + heightA;
int widthB = m_pBmpB->getSize().x;
int heightB = m_pBmpB->getSize().y;
int rightB = posB.x + widthB;
int bottomB = posB.y + heightB;
// bounding box test
if (rightA <= posB.x || posA.x >= rightB || bottomA <= posB.y || posA.y >= bottomB) {
return false;
}
// pixel level test
// calculate x overlap
int dX = posB.x - posA.x;
if (dX < 0) {
posA.x = 0;
posB.x = -dX;
}
else {
posA.x = dX;
posB.x = 0;
}
int width;
dX = rightB - rightA;
if (dX < 0)
width = std::min(widthA + dX, widthB);
else
width = std::min(widthB - dX, widthA);
// calculate y overlap
int dY = posB.y - posA.y;
if (dY < 0) {
posA.y = 0;
posB.y = -dY;
}
else {
posA.y = dY;
posB.y = 0;
}
int height;
dY = bottomB - bottomA;
if (dY < 0)
height = std::min(heightA + dY, heightB);
else
height = std::min(heightB - dY, heightA);
// test alpha channels
const unsigned char* pPixStartA = m_pBmpA->getPixels() +
(int) posA.y * m_pBmpA->getStride() +
(int) posA.x * 4 + 3; // alpha channel of 1st A pixel
const unsigned char* pPixStartB = m_pBmpB->getPixels() +
(int) posB.y * m_pBmpB->getStride() +
(int) posB.x * 4 + 3; // alpha channel of 1st B pixel
const unsigned char* pPixA = pPixStartA;
const unsigned char* pPixB = pPixStartB;
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
if (*pPixA && *pPixB) {
return true; // both pixels have alpha > 0 --> collision
}
pPixA += 4;
pPixB += 4;
}
pPixA = pPixStartA + y * m_pBmpA->getStride();
pPixB = pPixStartB + y * m_pBmpB->getStride();
}
return false;
}
} // namespace avg
using namespace boost::python;
BOOST_PYTHON_MODULE(collisiondetector)
{
class_<avg::CollisionDetector, boost::noncopyable>("CollisionDetector", no_init)
.def(init<avg::Bitmap&, avg::Bitmap&>())
.def("detect", &avg::CollisionDetector::detect)
;
}
AVG_PLUGIN_API void registerPlugin()
{
initcollisiondetector(); // created by BOOST_PYTHON_MODULE
object mainModule(handle<>(borrowed(PyImport_AddModule("__main__"))));
object collisiondetectorModule(handle<>(PyImport_ImportModule("collisiondetector")));
mainModule.attr("collisiondetector") = collisiondetectorModule;
}
|
