Just to add that the sample code i.e. "tiger" app given by OpenVG/Kornos has following configuration attributes:

EGLint egl_conf_attr[] = {
 	EGL_RED_SIZE,		8,
	EGL_GREEN_SIZE, 	8,
	EGL_BLUE_SIZE,		8,
	EGL_ALPHA_SIZE, 	8,
	EGL_LUMINANCE_SIZE, EGL_DONT_CARE,			
	EGL_SURFACE_TYPE,	EGL_WINDOW_BIT,
	EGL_SAMPLES,		1,
	EGL_NONE
}; 


The above configuration attributes dont work on my application. they fail at eglChooseConfig() call. Do I need to 
configure my hardware or do I need some different library for the same?

-Shivendra

Hi Shivendra,
	Unfortunately, the OpenVG driver for the iMX35 doesn't currently support multisampling, and that explains why you 
cannot choose a config with EGL_SAMPLE_BUFFERS set to 1.

Cheers,
Gaétan

-----Original Message-----
From: Shivendra Tiwari [mailto:community-noreply@qnx.com] 
Sent: June 18, 2009 4:58 PM
To: openvg-graphics
Subject: Antialiasing in OpenVG - on QNX ARM platform (IMX35 hardware)

Hello,

I am pretty new in the OpenVG application development. I am using OpenVG1.1 libraries for the same. I need to improve 
the line drawing quality in my existing QNX/ARM/IMX35 based application. 

The line drawing quality is not good in the existing app, therefore I want to apply Multi-sampling on the drawing, but 
not sure the correct method of applying it in OpenVG.

Following are the EGL config attributes I'm using in my application:

EGLint egl_conf_attr[] = {
    EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
    EGL_RENDERABLE_TYPE, EGL_OPENVG_BIT,
    EGL_DEPTH_SIZE, EGL_DONT_CARE,
    EGL_LEVEL, EGL_DONT_CARE,
    EGL_TRANSPARENT_TYPE, EGL_DONT_CARE,
    EGL_RED_SIZE, EGL_DONT_CARE,
    EGL_GREEN_SIZE, EGL_DONT_CARE,
    EGL_BLUE_SIZE, EGL_DONT_CARE,
    EGL_ALPHA_SIZE, EGL_DONT_CARE,
    EGL_BUFFER_SIZE, EGL_DONT_CARE,
    EGL_SAMPLE_BUFFERS, 0, /* value 1 doesn't work*/
    EGL_STENCIL_SIZE, EGL_DONT_CARE,
    EGL_SAMPLES, EGL_DONT_CARE,
    EGL_CONFIG_ID, EGL_DONT_CARE,
    EGL_NONE
};

I have already been using vgSeti(VG_IMAGE_QUALITY, VG_IMAGE_QUALITY_BETTER) API so that OpenVG applies anti-aliasing, 
but the line quality is still poor and lines are jagged.

As per OpenVG/EGL documents i.e. "openvg-1.1.pdf" and "eglspec.1.4.withchanges.20090422.pdf", EGL_SAMPLE_BUFFERS 
attribute can be used for multisampling. But setting the value of EGL_SAMPLE_BUFFERS as 1 (default is 0), fails the 
eglChooseConfig() API.  

Can someone let me know how to use multisampling (antialiasing) in OpenVG image drawing? Some sample code/example would 
be really helpful. Attached is the sample code I am using for the proof of concept which draws two diagonal lines.


Thanks a lot.
Shivendra

_______________________________________________
OpenVG
http://community.qnx.com/sf/go/post32076