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gl.vertexAttrib3f only lets you supply a single constant value to a GLSL attribute so you'll need to use gl.vertexAttribPointer and gl. 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 WebGL-whichAPItouse? AskQuestion Asked 8years,1monthago Modified 8years,1monthago Viewed 335times 0 1 Iwanttodrawmultiplepolygonshapes(whereeachshapehasit'sownsetofvertices). Iwanttobeabletopositiontheseshapesindependentlyofeachother. WhichAPIcaniusetosetthea_Positionforthevertexshader? A)gl.vertexAttrib3f B)gl.vertexAttribPointer+gl.enableVertexAttribArray thanks. opengl-eswebglvertex-arrayvertex-attributes Share Follow editedJun3,2014at3:39 AlvinfromDiaspar askedJun3,2014at3:33 AlvinfromDiasparAlvinfromDiaspar 6,3791313goldbadges6868silverbadges127127bronzebadges Addacomment  |  1Answer 1 Sortedby: Resettodefault Highestscore(default) Trending(recentvotescountmore) Datemodified(newestfirst) Datecreated(oldestfirst) 1 Yourquestionmakesitsoundlikeyou'rereallynewtoWebGL?Maybeyoushouldreadsometutorials?Butinanswertoyourquestion: gl.vertexAttrib3fonlyletsyousupplyasingleconstantvaluetoaGLSLattributesoyou'llneedtousegl.vertexAttribPointerandgl.enableVertexAttribArray.You'llalsoneedtosetupbufferswithyourvertexdata. gl.vertexAttrib3fonlypointisarguablytoletyoupassinaconstantinthecasethatyouhaveashaderthatusesmultipleattributesbutyoudon'thavedataforallofthem.Forexampleletssayyouhaveashaderthatusesbothtexturesandsoneedstexturecoordinatesanditalsohasvertexcolors.Somethinglikethis vertexshader attributevec4a_position; attributevec2a_texcoord; attributevec4a_color; varyingvec2v_texcoord; varyingvec4v_color; uniformmat4u_matrix; voidmain(){ gl_Position=u_matrix*a_position; //passtexcoordandvertexcolorstofragmentshader v_texcoord=a_texcoord; v_color=v_color; } fragmentshader precisionmediumpfloat; varyingvec2v_texcoord; varyingvec4v_color; uniformsampler2Du_texture; voidmain(){ vec4textureColor=texture2D(u_texture,v_texcoord); //multiplythetexturecolorbythevertexcolor gl_FragColor=textureColor*v_color; } Thisshaderrequiresvertexcolors.Ifyourgeometrydoesn'thavevertexcolorsthenyouhave2options(1)useadifferentshader(2)turnofftheattributeforvertexcolorsandsetittoaconstantcolor,probablywhite. gl.disableVertexAttribArray(aColorLocation); gl.vertexAttrib4f(aColorLocation,1,1,1,1); Nowyoucanusethesameshadereventhoughyouhavenovertexcolordata. Similarlyifyouhavenotexturecoordinatesyoucouldpassinawhite1pixelshaderandsetthetexturecoordinatestosomeconstant. gl.displayVertexAttribArray(aTexcoordLocation); gl.vertexAttrib2f(aTexcoordLocation,0,0); gl.bindTexture(gl.TEXTURE_2D,some1x1PixelWhiteTexture); Inthatcaseyoucouldalsodecidewhatcolortodrawwithbysettingthevertexcolorattribute. gl.vertexAttrib4f(aColorLocation,1,0,1,1);//drawinmagenta Share Follow editedJun3,2014at8:02 answeredJun3,2014at7:53 gmangman 93k2929goldbadges235235silverbadges349349bronzebadges 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?Browseotherquestionstaggedopengl-eswebglvertex-arrayvertex-attributesoraskyourownquestion. TheOverflowBlog HowStackOverflowislevelingupitsunittestinggame Developersvsthedifficultybomb(Ep.459) FeaturedonMeta Testingnewtrafficmanagementtool Duplicatedvotesarebeingcleanedup Trending:Anewanswersortingoption Updatedbuttonstylingforvotearrows:currentlyinA/Btesting Linked 1 gl_PositionwillnotmovevertexwhenIpassinpositiontoshaderwithattribute? 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