我創建box2d多邊形,我想創建夾具附着到身體的方法之外,但是當我這樣做,我得到一個訪問衝突。Box2d C++ AccessViolation使用b2fixture出方法
我已經通過了代碼,box2d肯定是獲取夾具對象。
當我將燈具附着到身體內部的方法,它工作正常。當我在調用方法嘗試它引發訪問衝突錯誤
b2FixtureDef* LineSegment::GenerateFixture(b2Vec2 vertices[4],b2Body* body,b2World* world){
b2BodyDef bodyDef;
//bodyDef.type = b2_kinematicBody;
bodyDef.position.Set(_currentStepStartPosition.x,_currentStepStartPosition.y);
body =world->CreateBody(&bodyDef);
int32 count = 4;
b2PolygonShape polygon;
polygon.Set(vertices, count);
b2FixtureDef fixtureDef2;
fixtureDef2.shape = &polygon;
fixtureDef2.density = 1.0f;
fixtureDef2.friction = 0.3f;
body->CreateFixture(&fixtureDef2);/// works if i attatch the fixture here here
return &fixtureDef2;
}
當我在此附上夾具失敗調用方法
bool LineSegment::GenerateNextBody(b2Body* retBody){
b2BodyDef bodyDef;
bodyDef.type = b2_staticBody;
bodyDef.position.Set(_currentStepStartPosition.x,_currentStepStartPosition.y);
retBody =world->CreateBody(&bodyDef);
_currentStep++;
b2Vec2 vertices[4];
if(_inclinePerStep != 0){
GetVertsInclineSquare(vertices,_stepWidth,_thickness,_inclinePerStep);
}else{
GetVertsSquare(vertices,_stepWidth,_thickness);
}
if(_currentStep == 1){
_GameWorldVerticies[0] =b2Vec2((_currentStepStartPosition.x+vertices[0].x)*PTM_RATIO,(_currentStepStartPosition.y+vertices[0].y)*PTM_RATIO);
_GameWorldVerticies[3] =b2Vec2((_currentStepStartPosition.x+vertices[3].x)*PTM_RATIO,(_currentStepStartPosition.y+vertices[3].y)*PTM_RATIO);
}
b2FixtureDef* fixture = GenerateFixture(vertices,retBody,world);
//retBody->CreateFixture(fixture); throws a access violation if i attatch the fixture here
_currentStepStartPosition.x += vertices[2].x+(vertices[2].x);
_currentStepStartPosition.y +=(_inclinePerStep/2);
if(_steps <= _currentStep){
_GameWorldVerticies[1] =b2Vec2((_currentStepStartPosition.x+vertices[1].x)*PTM_RATIO,(_currentStepStartPosition.y+vertices[1].y)*PTM_RATIO);
_GameWorldVerticies[2] =b2Vec2((_currentStepStartPosition.x+vertices[2].x)*PTM_RATIO,(_currentStepStartPosition.y+vertices[2].y)*PTM_RATIO);
return false;
}
return true;
}
UPDATE
新片段
b2FixtureDef* fixtureDef2 = new b2FixtureDef();
fixtureDef2->shape = &polygon;
fixtureDef2->density = 1.0f;
fixtureDef2->friction = 0.3f;
//body->CreateFixture(&fixtureDef2);/// works if i attatch the fixture here here
return fixtureDef2;
您是否嘗試過在調試器中運行程序?然後你可以捕捉到錯誤並檢查變量,看看它們是否全部看起來沒問題(即沒有「NULL」指針等)。 –
我知道程序崩潰的地方,我沒有看到任何可能導致空指針的東西。我應該粘貼調試數據(屏幕截圖和崩潰在box2d lib) – Billybonks