Cocos2dx雜記：PhysicsEditor 對應cocos2dx 3.x的接口封裝

PhysicsEditor是一款box2d形狀生成器，只需點點鼠標即可生成plist圖形文件，還有很有特色的魔術棒工具，可自動完成標記定點和分隔polygon的過程。可以直接在cocos2dx中使用。
如圖所示：可以對邊緣進行不規則圖形的選取

官方提供了Cocos2dx的第三方庫，但是採用的是2.x的接口，3.x下面依然是可以使用的，不過在這添加了採用3.x接口封裝的方法

void GB2ShapeCache::addShapesWithV3(const std::string &plist) {
    //const char *fullName = CCFileUtils::sharedFileUtils()->fullPathForFilename(plist.c_str()).c_str();

    auto dict = FileUtils::getInstance()->getValueMapFromFile(plist);
    //基礎屬性
    auto metadataDict = dict["metadata"].asValueMap();
    auto format = metadataDict["format"].asInt();
    ptmRatio = metadataDict["ptm_ratio"].asFloat();

    //body屬性]
    b2Vec2 vertices[b2_maxPolygonVertices];
    std::string bodyName;
    auto bodyDict = dict["bodies"].asValueMap();

    for (auto obj : bodyDict) {
        bodyName = obj.first;
        auto bodyData = bodyDict[bodyName].asValueMap();
        BodyDef *bodyDef = new BodyDef();
        bodyDef->anchorPoint = PointFromString(bodyData["anchorpoint"].asString());
        auto fixtureList = bodyData["fixtures"].asValueVector();
        FixtureDef **nextFixtureDef = &(bodyDef->fixtures);

        for (auto fixture : fixtureList) {
            b2FixtureDef basicData;
            ValueMap vecmap = fixture.asValueMap();

            basicData.density = vecmap["density"].asFloat();
            basicData.friction = vecmap["friction"].asFloat();
            basicData.restitution = vecmap["restitution"].asFloat();
            basicData.filter.categoryBits = vecmap["filter_categoryBits"].asInt();
            basicData.filter.groupIndex = vecmap["filter_groupIndex"].asInt();
            basicData.filter.maskBits = vecmap["filter_maskBits"].asFloat();
            basicData.isSensor = vecmap["isSensor"].asBool(); 

            std::string cb = vecmap["userdataCbValue"].asString();
            int callbackData = 0;
            if (cb.compare("") == 0) {
                callbackData = std::atoi(cb.c_str());
            }

            std::string fixtureType = vecmap["fixture_type"].asString();
            if (fixtureType == "POLYGON") {
                auto vec2Aarry = vecmap["polygons"].asValueVector();
                for (auto vec : vec2Aarry) {
                    FixtureDef *fix = new FixtureDef();
                    fix->fixture = basicData; // copy basic data
                    fix->callbackData = callbackData;

                    b2PolygonShape *polyshape = new b2PolygonShape();
                    int vindex = 0;

                    auto posArray = vec.asValueVector();

                    for (auto pos : posArray) {
                        Vec2 offset = PointFromString(pos.asString());
                        vertices[vindex].x = (offset.x / ptmRatio);
                        vertices[vindex].y = (offset.y / ptmRatio);
                        vindex++;
                    }

                    polyshape->Set(vertices, vindex);
                    fix->fixture.shape = polyshape;

                    // create a list
                    *nextFixtureDef = fix;
                    nextFixtureDef = &(fix->next);
                }
            }
            else if (fixtureType == "CIRCLE") {
                FixtureDef *fix = new FixtureDef();
                fix->fixture = basicData; // copy basic data
                fix->callbackData = callbackData;

                auto circleData = vecmap["circle"].asValueMap();

                b2CircleShape *circleShape = new b2CircleShape();

                circleShape->m_radius = circleData["radius"].asFloat() / ptmRatio;
                Vec2 p = PointFromString(circleData["position"].asString());
                circleShape->m_p = b2Vec2(p.x / ptmRatio, p.y / ptmRatio);
                fix->fixture.shape = circleShape;

                // create a list
                *nextFixtureDef = fix;
                nextFixtureDef = &(fix->next);
            }
            else {
                CCAssert(0, "Unknown fixtureType");
            }

        }
        // add the body element to the hash
        shapeObjects[bodyName] = bodyDef;
    }

1、使用方法

    // Load shapes，傳入PE工具生產的plist文件，一個具有不規則形狀的物理碰撞就實現了
    GB2ShapeCache::sharedGB2ShapeCache()->addShapesWithV3("sharp.plist");

2、下載地址

PhysicsEditor第三方庫