I got the same issue too. I used CCDrawNode::drawPolygon method to draw a polygon, the edge effects are bad.
Any solutions?
Help me. I have the same problem!!! My polygon can’t go antialiased 
I found a kind of solution- use CCRenderTexture and convert your poly to CCSprite- it is antialiased by default.
I have the same problem.
I’ve tried to restore the commented code in ccShader_PositionColorLengthTexture_frag.h, but there’s no effect.
There’s some way to draw antialiased primitives with DrawNode without using a RenderTexture?
In fact, I’m not able to draw an antialiased image of the layer using a RenderTexture either.
The image quality using a RenderTexture is low, and I don’t get a quality antialiasing if I scale down the node.
I have attached some images to show the problem.
void HelloWorld::update(float delta)
{
Layer::update(delta);
mRenderTextureSprite->setVisible(false);
Size visibleSize = Director::getInstance()->getVisibleSize();
mRenderTexture = RenderTexture::create(visibleSize.width, visibleSize.height, Texture2D::PixelFormat::RGBA8888);
mRenderTexture->begin();
visit();
mRenderTexture->end();
auto finalTexture = mRenderTexture->getSprite()->getTexture();
finalTexture->setAntiAliasTexParameters();
mRenderTextureSprite->setTexture(finalTexture);
Rect rect = Rect::ZERO;
rect.size = finalTexture->getContentSize();
mRenderTextureSprite->setTextureRect(rect);
//mRenderTextureSprite->cocos2d::Node::setScale(0.5);
mRenderTextureSprite->setBlendFunc(BlendFunc::ALPHA_PREMULTIPLIED);
mRenderTextureSprite->setVisible(true);
}
I found it!
In order to draw antialiased primitives, you have to force smoothstep:
" \n\
#ifdef GL_ES \n\
// #extension GL_OES_standard_derivatives : enable \n\
\n\
varying mediump vec4 v_color; \n\
varying mediump vec2 v_texcoord; \n\
#else \n\
varying vec4 v_color; \n\
varying vec2 v_texcoord; \n\
#endif \n\
\n\
void main() \n\
{ \n\
// #if defined GL_OES_standard_derivatives \n\
// gl_FragColor = v_color*smoothstep(0.0, length(fwidth(v_texcoord)), 1.0 - length(v_texcoord)); \n\
// #else \n\
// gl_FragColor = v_color*step(0.0, 1.0 - length(v_texcoord)); \n\
// #endif \n\
gl_FragColor = v_color*smoothstep(0.0, length(fwidth(v_texcoord)), 1.0 - length(v_texcoord)); \n\
} \n\
";
@Chano,
I tried the code on iOS device and I got this error :
cocos2d: cocos2d: ERROR: 0:29: Call to undeclared function 'fwidth'
@barisatamer
It seems on iOS you have to enable GL_OES_standard_derivatives.
I don’t have an iOS device to test it, but probably if you uncomment all the commented code in the shader fwidth will work:
http://stackoverflow.com/questions/9671705/opengl-es-2-0-derivative-texture
This helped me in iOS, but the anti-alias issues persists on Mac desktop (Mavericks). Any further ideas?
Correction, it worked in the simulator, not in an ipad mini retina, for instance. =/
Weird, I tested it some time ago on a Mac Mini with Mountain Lion and it worked without problems.
@Chano I overlooked your actual code, i.e., the gl_FragColor definition is outside the conditional blocks. I see it working now, thanks! Will have to test it in Android now.
Cheers!
I think I jumped the gun again, this worked in the Mac build, and never in the iOS device. Still sifting through options.
@hcabral
I have it working on Windows and some Android devices like the Nexus 4 (in other Android devices the app is aborted because this: http://cocos2d-x.org/forums/6/topics/51698?r=51897).
As I said, I tested it on a Mac Mini too. But I haven’t tested it on an iOS device because I don’t have one 
I will check it on Android, just for kicks now.
It works on iOS, OSX, win32 and Android. Am using v2.2.2.
@IslandPlaya it didn’t work for me in iOS 7.1.1. Works in the simulator, not in the actual device. I’ve tried an iPhone 5s and iPad Mini Retina.
@Chano Android worked too.
Thanks for the info hcabral.
I don’t have a 7.1.1 device to test on, but I will be sure to look into this before my game is released.
Many thanks.
@mikolaj_o would you mind further explaining your solution? I have the antialias effect working on a Mac, Android but no success on iOS devices.
I have finally managed to make it work on iOS devices with the following code based on the primitives test. Here’s the .h:
class Circle : public cocos2d::Layer
{
private:
void onDrawPrimitives(const kmMat4 &transform, bool transformUpdated);
cocos2d::CustomCommand _customCommand;
public:
Circle();
virtual void draw(cocos2d::Renderer *renderer, const kmMat4 &transform, bool transformUpdated) override;
};
And the cpp:
#include "Circle.h"
USING_NS_CC;
Circle::Circle()
{
}
void Circle::onDrawPrimitives(const kmMat4 &transform, bool transformUpdated)
{
kmGLPushMatrix();
kmGLLoadMatrix(&transform);
Size visibleSize = Director::getInstance()->getVisibleSize();
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
glLineWidth(1);
color4B(255, 0, 255, 255);
DrawPrimitives::drawSolidCircle(Point(visibleSize.width/2, visibleSize.height/2), 60, 0, 30, 1, 1);
}
void Circle::draw(Renderer *renderer, const kmMat4& transform, bool transformUpdated)
{
_customCommand.init(_globalZOrder);
_customCommand.func = CC_CALLBACK_0(Circle::onDrawPrimitives, this, transform, transformUpdated);
renderer->addCommand(&_customCommand);
}
I’m almost hitting a point where I will either #if #elif this to use drawnode or my custom layer class depending on the platform, since the shader modification does the job on a Mac and Android.
Even though I’m not very experienced in Cocos2d-x or OpenGL, I would greatly appreciate some insight to answer this question.
Cheers,
Henrique