Smooth line drawing, glsl, shader, openframeworks, sketch

Smooth line drawing, glsl, shader, openframeworks, sketch - ofApp.cpp. ... I draw the lines as one big vboMesh, each line has 2 polygons, ... Skiptocontent Allgists BacktoGitHub Signin Signup Sign in Sign up {{message}} Instantlysharecode,notes,andsnippets. gwio/ofApp.cpp CreatedMay13,2018 Star 1 Fork 0 Star Code Revisions 1 Stars 1 Embed Whatwouldyouliketodo? Embed Embedthisgistinyourwebsite. Share Copysharablelinkforthisgist. Clonevia HTTPS ClonewithGitorcheckoutwithSVNusingtherepository’swebaddress. LearnmoreaboutcloneURLs DownloadZIP Smoothlinedrawing,glsl,shader,openframeworks,sketch Raw ofApp.cpp ThisfilecontainsbidirectionalUnicodetextthatmaybeinterpretedorcompileddifferentlythanwhatappearsbelow.Toreview,openthefileinaneditorthatrevealshiddenUnicodecharacters. LearnmoreaboutbidirectionalUnicodecharacters Showhiddencharacters /*IdrawthelinesasonebigvboMesh,eachlinehas2polygons,theyareconstructedfromthesamevertexpositionand andextrudedlaterinthevertexshader*/ lineMesh.addVertex(lineStart); lineMesh.addVertex(lineEnd); lineMesh.addVertex(lineEnd); lineMesh.addVertex(lineStart); //...lineMesh.addIndex(..)...addingtheindexorder //thisisthenormalvectortooffsettheverticeslater ofVec2fnormalLine=(lineStart-lineEnd).getPerpendicular(); /*normalLinegetsintoavector,2floatsforeachvertex,itsjustimportantthateverymeshvertexhasown normal"linewidth"vectorbothpositiveandnegativedirection*/ lineNormalVec.push_back(normalLine.x); lineNormalVec.push_back(normalLine.y); /*ThelineNormalVecisthenusedascustomattributefortheshader*/ shader.setupShaderFromFile(GL_VERTEX_SHADER,"shader.vert"); shader.setupShaderFromFile(GL_FRAGMENT_SHADER,"shader.frag"); shader.bindDefaults(); //0-4arealreadyusedbyof shader.bindAttribute(5,"line_Normals"); shader.linkProgram(); intshaderAttPos=shader.getAttributeLocation("line_Normals"); lineMesh.getVbo().setAttributeData(shaderAttPos,lineNormalVec[0],2,lineNormalVec.size(),GL_STATIC_DRAW,sizeof(float)*2); //thelinesarethedrawnintoafbo shader.begin(); fbo.begin(); ofClear(0,0,0,255); shader.setUniform1f("time",ofGetElapsedTimef()/4.0); //notsurewhatthe"right"settingsarebuttheglBlendEquation(max)isimportant, glDisable(GL_CULL_FACE); glDisable(GL_DEPTH_TEST); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA,GL_ZERO); //thisworksonios;glBlendEquationOES(GL_MAX_EXT); glBlendEquation(GL_MAX); drawLineMesh(); fbo.end(); shader.end(); //Ithenlaterthisfboandprocessitwithanothershaderforcoloringandlinecaps Raw shader.frag ThisfilecontainsbidirectionalUnicodetextthatmaybeinterpretedorcompileddifferentlythanwhatappearsbelow.Toreview,openthefileinaneditorthatrevealshiddenUnicodecharacters. LearnmoreaboutbidirectionalUnicodecharacters Showhiddencharacters /*thismakesthelinesmooth,agradient,basedonthefragmentpositioninsidethelinepolygon.Iusepow()to tomodifythegradientcurve,hardergradientforbiggerwidth,smoothercurveforthinlines.Alsothereareprobably betterwaysthenusingpow()forthis.*/ invec2frag_pos; voidmain() { vec2pos; pos.x=gl_FragCoord.x; pos.y=gl_FragCoord.y; vec2xy=frag_pos-gl_FragCoord.xy; //floatalpha=pow(length(frag_pos),abs(sin(time)*6)+2); floatalpha=pow(length(frag_pos),5); vec4tempOut=vec4(0,0,0,0); outputColor=vec4(1.0-alpha,1.0-alpha,1.0-alpha,1.0); } Raw shader.vert ThisfilecontainsbidirectionalUnicodetextthatmaybeinterpretedorcompileddifferentlythanwhatappearsbelow.Toreview,openthefileinaneditorthatrevealshiddenUnicodecharacters. LearnmoreaboutbidirectionalUnicodecharacters Showhiddencharacters #version150 uniformmat4modelViewProjectionMatrix; uniformfloattime; invec2line_Normals; invec4position; invec2texcoord; outvec2texCoordVarying; outvec2frag_pos; voidmain(){ //thenormalvecotrisscaledbythedesiredlinewidthandappliedtoeachvertex vec4delta=vec4(line_Normals*"lineWidht",0,0); vec4pos=modelViewProjectionMatrix*(position+delta); texCoordVarying=vec2(texcoord.x,texcoord.y); frag_pos=line_Normals; gl_Position=pos; } Raw shader2.frag ThisfilecontainsbidirectionalUnicodetextthatmaybeinterpretedorcompileddifferentlythanwhatappearsbelow.Toreview,openthefileinaneditorthatrevealshiddenUnicodecharacters. LearnmoreaboutbidirectionalUnicodecharacters Showhiddencharacters /*Ithenuseasecondshadertofillthegapsbetweenthelineswithcircles,withasimilargradient, thisisabittrickyandtotallynotperfect,butdecentenough;)*/ floatradius=(18.0*abs(sin(time))+1.0)*1.08; //floatradius=(2.5)*1.08; vec4imageC=texture(net,texCoordVarying); vec4addCircle=vec4(1.0,1.0,1.0,1.0); floatalpha=0.0; for(inti=0;i