Question

我是cocos2d-x的新手，我正在尝试在其中绘制带有颜色的圆圈。我在网上搜索，我发现了一些代码。我尝试下面的代码，但它只绘制带有彩色边框的圆圈。我的cocos2d-x版本是2.1.5，我用它来安装android。我还尝试使用此方法更改边框的宽度： glLineWidth（2）; 但在我的cocos2d-x中找不到此方法。如何在圆圈中添加颜色以及如何更改圆圈边框的宽度。

cocos2d::ccDrawColor4B(0, 255, 255, 255);
cocos2d::ccDrawColor4F(0, 255, 255, 255);
cocos2d::ccDrawCircle( ccp(100/2, 100/2), 50, CC_DEGREES_TO_RADIANS(90), 50, false);

Answer 1

在CCDrawNode课程中，您可以绘制圆形，线条和多边形。

void drawDot(const CCPoint & pos,float  radius, const ccColor4F & color)

在一个具有给定半径和颜色的位置绘制一个填充圆

Answer 2

不确定哪个cocos2d-x版本可用，但您应该有一个特定的方法来绘制实心圆圈.-

void drawSolidCircle( const Point& center, float radius, float angle, unsigned int segments, float scaleX, float scaleY);

看看夜间CCDrawingPrimitives.cpp课程。

Answer 3

只需在CCDrawingPrimitives中添加一个新方法。除ccDrawCircle使用glDrawArrays代替GL_TRIANGLE_FAN

外，它与GL_LINE_STRIP相同

在标题中，添加：

 void CC_DLL ccDrawSolidCircle( const CCPoint& center, float radius, float angle, unsigned int segments, bool drawLineToCenter);

在.cpp文件中，添加：

 void ccDrawSolidCircle( const CCPoint& center, float radius, float angle, unsigned int segments, bool drawLineToCenter)
 {
lazy_init();

float scaleX = 1;
float scaleY = 1;

int additionalSegment = 1;
if (drawLineToCenter)
    additionalSegment++;

const float coef = 2.0f * (float)M_PI/segments;

GLfloat *vertices = (GLfloat*)calloc( sizeof(GLfloat)*2*(segments+2), 1);
if( ! vertices )
    return;

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

    vertices[i*2] = j;
    vertices[i*2+1] = k;
}
vertices[(segments+1)*2] = center.x;
vertices[(segments+1)*2+1] = center.y;

s_pShader->use();
s_pShader->setUniformsForBuiltins();
s_pShader->setUniformLocationWith4fv(s_nColorLocation, (GLfloat*) &s_tColor.r, 1);

ccGLEnableVertexAttribs( kCCVertexAttribFlag_Position );

 #ifdef EMSCRIPTEN
setGLBufferData(vertices, sizeof(GLfloat)*2*(segments+2));
glVertexAttribPointer(kCCVertexAttrib_Position, 2, GL_FLOAT, GL_FALSE, 0, 0);
 #else
glVertexAttribPointer(kCCVertexAttrib_Position, 2, GL_FLOAT, GL_FALSE, 0, vertices);
 #endif // EMSCRIPTEN
glDrawArrays(GL_TRIANGLE_FAN, 0, (GLsizei) segments+additionalSegment);

free( vertices );

CC_INCREMENT_GL_DRAWS(1);
 }

如何在cocos2d-x中用颜色绘制圆形填充？

3 个答案: