cocos2dx画扇形

代码参考于：http://www.allareone.cn/?p=36#more-36
非常感谢！
先把大神的文章摘取如下：

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由于项目需求，但是cocos2dx的却没有提供画扇形和环形的函数，于是乎决定自己写一个画扇形的函数。
基于cocos2dx-3.3版本继承于DrawNode类

就不详解了，感情都在代码里了:）, 有需要请取走
用法示例： drawSolidSector(Vec2(200,200), Vec2(1,1), 100, 150, M_PI, 40, Color4F(1, 0, 0, 1));

void MyDrawNode::drawSolidSector(const Vec2 &orign,const Vec2 &beginVec, const float radius1, const float radius2, const float radian, const int segments, const cocos2d::Color4F &color)
{
    float angle = atanf(beginVec.x / beginVec.y);
    angle = beginVec.y<0? angle+M_PI: angle;
    float coef = radian/segments;
    Vec2 *vertices1 = new (std::nothrow) Vec2[segments+1];
    if( ! vertices1 )
        return;

    Vec2 *vertices2 = new (std::nothrow) Vec2[segments+1];
    if( ! vertices2 )
        return;

    for(unsigned int i = 0;i <= segments; i++)
    {
        float rads = i*coef;
        GLfloat j = radius1 * cosf(rads + angle) + orign.y;
        GLfloat k = radius1 * sinf(rads + angle) + orign.x;

        vertices1[i].x = k;
        vertices1[i].y = j;

        GLfloat l = radius2 * cosf(rads + angle) + orign.y;
        GLfloat m = radius2 * sinf(rads + angle) + orign.x;

        vertices2[i].x = m;
        vertices2[i].y = l;
    }

    V2F_C4B_T2F_Triangle *triangles = new V2F_C4B_T2F_Triangle[segments*2];

    int triCount = 0;
    for (int i=0; i1];

        triangles[triCount].a.vertices = vertices1[i];
        triangles[triCount].b.vertices = vertices1[i+1];
        triangles[triCount++].c.vertices = vertices2[i+1];
    }

    for (int i=0; i2; i++) {
        drawTriangle(triangles[i].a.vertices, triangles[i].b.vertices, triangles[i].c.vertices, color);
    }

    CC_SAFE_DELETE_ARRAY(vertices1);
    CC_SAFE_DELETE_ARRAY(vertices2);
    CC_SAFE_DELETE_ARRAY(triangles);
}

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饼状图/抽奖的效果

代码实现：

auto drawNode = DrawNode::create();
    //测试的角度
    //float radian[] = { 15.0f, 30.0f, 45.0f, 75.0f, 90.0f, 105.0f };
    float radian[] = { 60.0f, 60.0f, 60.0f, 60.0f, 60.0f, 60.0f };
    //扇形半径
    float RADIUS = 300.0f;
    //坐标偏移量
    float beginVec = 0.0f;
    //字体偏移量
    float middleVec = 0.0f;
    //旋转字体
    float rotation = 0.0f;
    for (int i = 0; i < sizeof(radian) / sizeof(radian[0]); i++)
    {
        //坐标
        float x = sin(beginVec);
        float y = cos(beginVec);

        //颜色
        float r = rand_0_1();
        float g = rand_0_1();
        float b = rand_0_1();

        //画弧形
        drawNode->drawSolidSector(Vec2(900, 400), Vec2(x, y), RADIUS, 0, radian[i] * M_PI / 180.0f, 200, Color4F(r, g, b, 1));
        beginVec = beginVec + radian[i] * M_PI / 180.0f;


        //度数字体
        string txt = StringUtils::format("%.f", radian[i]);
        auto text = Text::create(txt, "", 30.0f);
        middleVec = radian[i] / 2 * M_PI / 180.0f;
        text->setPosition(Vec2(900 + RADIUS/2 *  sin(beginVec - middleVec), 400 + RADIUS/2 * cos(beginVec - middleVec)));
        text->setRotation(rotation + radian[i] / 2); //旋转
        rotation += radian[i];
        addChild(text, 2);
    }
    addChild(drawNode, 1);