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QuestionXna object Transformation. PinmemberAghaKhan22-Oct-11 21:56 
Questionfree or affordable software for the editing of the photo [modified] Pinmemberanthonybates11-Jul-11 19:06 
AnswerRe: free or affordable software for the editing of the photo PinmemberDrew Stainton11-Jul-11 19:38 
QuestionGraphics Plugin for Liquidity Risk Software? PinmemberStaceyL21-Jun-11 11:46 
Jokei want to Pinmemberyexiaofeng18-Apr-11 23:05 
Questionhai PinmemberSR Baby31-Mar-11 23:32 
QuestionProblem with compression of a DirectShow video filter Pinmember428814-Jan-11 8:05 
Question[OpenGL/MFC/C++] backface transparency... PinmemberMaximilien11-Jan-11 6:02 
(OpenGL on vs2008)
I'm drawing surfaces, not volumes. the issue is corruption (or maybe PEBKAC) when displaying "blended" (transparent)
I don't seem to understand how the surface must be "setup" to obtain full surface transparency on both the front side and back side.

I have something like :
::glReadBuffer( GL_BACK );
::glDrawBuffer( GL_BACK );
::glDepthFunc( GL_LESS );
::glEnable( GL_DEPTH_TEST );

// init.
glPolygonMode ( GL_FRONT, GL_FILL );
glPolygonMode ( GL_BACK, GL_FILL  );
glDepthMask( GL_FALSE );
glEnable( GL_BLEND );
glColor4ub( red, green, blue, alpha ); //valid values.
// draw the cone (render triangles)...

// cleanup...
glDisable( GL_BLEND );
glDepthMask( GL_TRUE );
When using this code, there are some corruption in the display, surface "patches" are not rendered appropriately when displaying against "itself", for example a front facing polygon of a cone or cylinder which is displayed against a back" face of the same cone or cylinder.
see images showing the issue:
simple cylinder :[^]
a cone, a sphere and a plane.[^]

Watched code never compiles.

AnswerRe: [OpenGL/MFC/C++] backface transparency... Pinmemberjk chan14-Jan-11 5:42 
AnswerRe: [OpenGL/MFC/C++] backface transparency... Pinmemberparths19-Jan-11 3:49 
Questiontransparent using Fillpath Pinmembertransoft9-Jan-11 16:19 
AnswerRe: transparent using Fillpath PinmvpRichard MacCutchan10-Jan-11 0:28 
QuestionOpenGL rendering on desktop [modified] PinmemberTcpip200519-Dec-10 2:17 
AnswerRe: OpenGL rendering on desktop Pinmemberparths22-Dec-10 23:28 
GeneralRe: OpenGL rendering on desktop PinmemberTcpip200524-Dec-10 3:06 
AnswerRe: OpenGL rendering on desktop PinmemberDrew Stainton30-Dec-10 13:46 
GeneralRe: OpenGL rendering on desktop PinmemberTcpip200531-Dec-10 18:51 
Questiontransparently blit a bitmap Pinmembermike7521413-Dec-10 10:01 
AnswerRe: transparently blit a bitmap PinmemberLunaticFringe13-Dec-10 13:00 
AnswerRe: transparently blit a bitmap Pinmemberjk chan27-Dec-10 2:00 
QuestionGraphics.FillPath( Brush, GraphicsPath ) does not fill a simple Path. PinmemberWDI28-Oct-10 3:47 
AnswerRe: Graphics.FillPath( Brush, GraphicsPath ) does not fill a simple Path. PinmemberRaviRanjankr13-Dec-10 19:49 
Questiontool for real time graph plotting.. Pinmemberjainiraj27-Oct-10 2:21 
AnswerCross Post! PinmvpHenry Minute27-Oct-10 2:41 
GeneralRe: Cross Post! Pinmemberjainiraj27-Oct-10 5:18 

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