GLSL vertex shader gl_Position value - opengl - Stack Overflow

I'm trying to understand the value of gl_Position in vertex shader. ... and y coordinates translate to screen position in range of -1 to 1, ... 2022DeveloperSurveyisopen!Takesurvey. Home Public Questions Tags Users Companies Collectives ExploreCollectives Teams StackOverflowforTeams –Startcollaboratingandsharingorganizationalknowledge. CreateafreeTeam WhyTeams? Teams CreatefreeTeam Collectives™onStackOverflow Findcentralized,trustedcontentandcollaboratearoundthetechnologiesyouusemost. Learnmore Teams Q&Aforwork Connectandshareknowledgewithinasinglelocationthatisstructuredandeasytosearch. Learnmore GLSLvertexshadergl_Positionvalue AskQuestion Asked 7years,1monthago Modified 7years,1monthago Viewed 6ktimes 2 I'mcreatinggamethatusesorthogonalview(2D).I'mtryingtounderstandthevalueofgl_Positioninvertexshader. FromwhatIunderstandxandycoordinatestranslatetoscreenpositioninrangeof-1to1,butI'mquiteconfusedwithroleofthezandw,Ionlyknowthatthewvalueshouldbesetto1.0 ForthemomentIjustusegl_Position.xyw=vec3(Position,1.0);,wherePositionis2Dvertexposition IuseOpenGL3.2. openglglslopengl-3 Share Improvethisquestion Follow askedApr1,2015at16:11 Magik6kMagik6k 10522silverbadges88bronzebadges Addacomment  |  1Answer 1 Sortedby: Resettodefault Highestscore(default) Datemodified(newestfirst) Datecreated(oldestfirst) 4 RememberthatopenGLmustalsoworkfor3Dandit'seasiertoexposethe3Ddetailsthantocreateanewinterfaceforjust2D. TheZcomponentistosetthedepthofthevertex,pointsoutside-1,1(afterperspectivedivide)willnotbedrawnandforthevaluesbetween-1,1itwillbecheckedagainstadepthbuffertoseeifthefragmentisbehindsomepreviouslydrawntriangleandnotdrawitifitshouldbehidden. ThewcomponentisforaperspectivedivideandallowingtheGPUtointerpolatethevaluesinaperspectivecorrectway.Otherwisethetextureslooksweird. Share Improvethisanswer Follow answeredApr1,2015at16:17 ratchetfreakratchetfreak 45.9k55goldbadges6363silverbadges102102bronzebadges 1 1 Oh,Ididn'tthinkofdepthneedatthisstage.Thanksforexplaining! – Magik6k Apr1,2015at16:27 Addacomment  |  YourAnswer ThanksforcontributingananswertoStackOverflow!Pleasebesuretoanswerthequestion.Providedetailsandshareyourresearch!Butavoid…Askingforhelp,clarification,orrespondingtootheranswers.Makingstatementsbasedonopinion;backthemupwithreferencesorpersonalexperience.Tolearnmore,seeourtipsonwritinggreatanswers. Draftsaved Draftdiscarded Signuporlogin SignupusingGoogle SignupusingFacebook SignupusingEmailandPassword Submit Postasaguest Name Email Required,butnevershown PostYourAnswer Discard Byclicking“PostYourAnswer”,youagreetoourtermsofservice,privacypolicyandcookiepolicy Nottheansweryou'relookingfor?Browseotherquestionstaggedopenglglslopengl-3oraskyourownquestion. 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