【麦可网】Cocos2d-X跨平台游戏开发学习笔记---第十六课：Cocos2D-X几何图形1-3-优快云博客

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【麦可网】Cocos2d-X跨平台游戏开发---学习笔记

第十六课：Cocos2D-X几何图形1-3

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课程目标：

- Cocos2D-X几何图形绘制

课程重点：

- Cocos2D-X几何图形绘制

- Cocos2D-X节点理解

考核目标：

- Cocos2D-X几何图形绘制

- Cocos2D-X节点理解

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一、几何图形绘制

参考代码：tests->DrawPrimitives Test


void DrawPrimitivesTest::draw()
{
    
	CHECK_GL_ERROR_DEBUG();
    
	// draw a simple line
	// The default state is:
	// Line Width: 1
	// color: 255,255,255,255 (white, non-transparent)
	// Anti-Aliased
//	glEnable(GL_LINE_SMOOTH);
//直线绘制
    ccDrawLine( VisibleRect::leftBottom(), VisibleRect::rightTop() );
    
	CHECK_GL_ERROR_DEBUG();
    
	// line: color, width, aliased
	// glLineWidth > 1 and GL_LINE_SMOOTH are not compatible
	// GL_SMOOTH_LINE_WIDTH_RANGE = (1,1) on iPhone
//	glDisable(GL_LINE_SMOOTH);
	glLineWidth( 5.0f );	//设置线的宽度，opengl的设置将会影响后面的画线
//设置颜色
	ccDrawColor4B(255,0,0,255);
    ccDrawLine( VisibleRect::leftTop(), VisibleRect::rightBottom() );
    
	CHECK_GL_ERROR_DEBUG();
    
	// TIP:
	// If you are going to use always the same color or width, you don't
	// need to call it before every draw
	//
	// Remember: OpenGL is a state-machine.
    
	// draw big point in the center
//改变点的尺寸和颜色
	ccPointSize(64);
	ccDrawColor4B(0,0,255,128);
    ccDrawPoint( VisibleRect::center() );
    
	CHECK_GL_ERROR_DEBUG();
    
	// draw 4 small points
//绘制四个点
	CCPoint points[] = { ccp(60,60), ccp(70,70), ccp(60,70), ccp(70,60) };
	ccPointSize(4);
	ccDrawColor4B(0,255,255,255);
	ccDrawPoints( points, 4);
    
	CHECK_GL_ERROR_DEBUG();
    
	// draw a green circle with 10 segments
//绘制10段的圆
	glLineWidth(16);
	ccDrawColor4B(0, 255, 0, 255);
//参数依次是：1.中心点 2.半径 3.角度 4.几段 5.是否画一条半径
    ccDrawCircle( VisibleRect::center(), 100, 0, 10, false);
    
	CHECK_GL_ERROR_DEBUG();
    
	// draw a green circle with 50 segments with line to center
	glLineWidth(2);
	ccDrawColor4B(0, 255, 255, 255);
    ccDrawCircle( VisibleRect::center(), 50, CC_DEGREES_TO_RADIANS(90), 50, true);
    
	CHECK_GL_ERROR_DEBUG();
    
	// open yellow poly
//绘制指定5个点的多边形
	ccDrawColor4B(255, 255, 0, 255);
	glLineWidth(10);
	CCPoint vertices[] = { ccp(0,0), ccp(50,50), ccp(100,50), ccp(100,100), ccp(50,100) };
	ccDrawPoly( vertices, 5, false);
    
	CHECK_GL_ERROR_DEBUG();
	
	// filled poly
//绘制填充颜色的多边形
	glLineWidth(1);
	CCPoint filledVertices[] = { ccp(0,120), ccp(50,120), ccp(50,170), ccp(25,200), ccp(0,170) };
	ccDrawSolidPoly(filledVertices, 5, ccc4f(0.5f, 0.5f, 1, 1 ) );
    
    
	// closed purble poly
//绘制紫色的闭合图形
	ccDrawColor4B(255, 0, 255, 255);
	glLineWidth(2);
	CCPoint vertices2[] = { ccp(30,130), ccp(30,230), ccp(50,200) };
	ccDrawPoly( vertices2, 3, true);
    
	CHECK_GL_ERROR_DEBUG();
    
	// draw quad bezier path
//绘制四次贝塞尔曲线
    ccDrawQuadBezier(VisibleRect::leftTop(), VisibleRect::center(), VisibleRect::rightTop(), 50);
    
	CHECK_GL_ERROR_DEBUG();
    
	// draw cubic bezier path
//绘制三次贝塞尔曲线 
    ccDrawCubicBezier(VisibleRect::center(), ccp(VisibleRect::center().x+30,VisibleRect::center().y+50), ccp(VisibleRect::center().x+60,VisibleRect::center().y-50),VisibleRect::right(),100);
    
	CHECK_GL_ERROR_DEBUG();
    
    //draw a solid polygon
	CCPoint vertices3[] = {ccp(60,160), ccp(70,190), ccp(100,190), ccp(90,160)};
//ccc4f，参数既可以是0-1，也可以是0-255
    ccDrawSolidPoly( vertices3, 4, ccc4f(1,1,0,1) );		
    
	// restore original values
//恢复原始值
	glLineWidth(1);
	ccDrawColor4B(255,255,255,255);
	ccPointSize(1);
    
	CHECK_GL_ERROR_DEBUG();
}