0027633: Visualization, TKOpenGl - point sprites are inconsistent within Core and Compatible Profiles

OpenGl_ShaderManager::pointSpriteAlphaSrc() now does not return alpha from Red channel
for RGBA marker texture in Core profile.
OpenGl_ShaderManager::prepareStdProgramFlat() - restored code for drawing points without texture.

Built-in GLSL programs now flip .y in shaders instead of
relying on GL_POINT_SPRITE_COORD_ORIGIN unavailable on OpenGL ES.

Added sample markers.tcl (moved from test cases).
Sample now includes marker_kr.png for testing marker orientation.

samples/tcl/markers.tcl

@@ -0,0 +1,74 @@
+# Markers demo
+#
+# It shows the various marker types supported by OCCT.
+
+#Category: Visualization
+#Title: Markers in 3d viewer
+
+pload MODELING VISUALIZATION
+
+# reflects Aspect_TypeOfMarker enumeration
+set aMarkerTypeNames {
+  Aspect_TOM_POINT
+  Aspect_TOM_PLUS
+  Aspect_TOM_STAR
+  Aspect_TOM_X
+  Aspect_TOM_O
+  Aspect_TOM_O_POINT
+  Aspect_TOM_O_PLUS
+  Aspect_TOM_O_STAR
+  Aspect_TOM_O_X
+  Aspect_TOM_RING1
+  Aspect_TOM_RING2
+  Aspect_TOM_RING3
+  Aspect_TOM_BALL
+  Aspect_TOM_USERDEFINED
+}
+
+# custom marker
+set aCustom1 [locate_data_file images/marker_box1.png]
+set aCustom2 [locate_data_file images/marker_box2.png]
+set aCustom3 [locate_data_file images/marker_kr.png]
+set aCustom4 [locate_data_file images/marker_dot.png]
+
+set aFontFile [locate_data_file DejaVuSans.ttf]
+set aLabelFont "Arial"
+if { "$aFontFile" != "" } {
+  vfont add "$aFontFile" SansFont
+  set aLabelFont "SansFont"
+}
+
+# reset the viewer
+vclear
+vclose ALL
+vinit name=View1 l=32 t=32 w=512 h=512
+
+puts "Draw box in advance which should fit all our markers"
+box b -8 -8 0 16 16 2
+vbottom
+vdisplay -noupdate -dispmode 0 b
+vfit
+vremove -noupdate b
+
+puts "Draw markers of different type and size"
+for { set aMarkerType 0 } { $aMarkerType <= 13 } { incr aMarkerType } {
+  set aRow [expr $aMarkerType - 7]
+  set aCol 5
+  set aName [lindex $aMarkerTypeNames $aMarkerType]
+  vdrawtext "$aName" "$aName" -pos 0 [expr $aRow + 0.5] 0 -color 0.5 1.0 1.0 -halign center -valign center -angle 000 -zoom 0 -height 12 -aspect bold -font $aLabelFont
+  if { $aMarkerType == 13 } {
+    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom1
+    set aCol [expr $aCol - 1]
+    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom2
+    set aCol [expr $aCol - 1]
+    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom3
+    set aCol [expr $aCol - 1]
+    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom4
+  } else {
+    for { set aMarkerScale 1.0 } { $aMarkerScale <= 7 } { set aMarkerScale [expr $aMarkerScale + 0.5] } {
+      vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 MarkerType=$aMarkerType Scale=$aMarkerScale PointsOnSide=1
+      set aCol [expr $aCol - 1]
+    }
+  }
+}
+puts "All markers have been displayed"

src/OpenGl/OpenGl_Context.cxx

@@ -138,8 +138,10 @@ OpenGl_Context::OpenGl_Context (const Handle(OpenGl_Caps)& theCaps)
   myIsStereoBuffers (Standard_False),
   myIsGlNormalizeEnabled (Standard_False),
 #if !defined(GL_ES_VERSION_2_0)
+  myPointSpriteOrig (GL_UPPER_LEFT),
   myRenderMode (GL_RENDER),
 #else
+  myPointSpriteOrig (0),
   myRenderMode (0),
 #endif
   myReadBuffer (0),
@@ -2742,6 +2744,27 @@ void OpenGl_Context::SetPointSize (const Standard_ShortReal theSize)
 #endif
 }
 
+// =======================================================================
+// function : SetPointSpriteOrigin
+// purpose  :
+// =======================================================================
+void OpenGl_Context::SetPointSpriteOrigin()
+{
+#if !defined(GL_ES_VERSION_2_0)
+  if (core15fwd == NULL)
+  {
+    return;
+  }
+
+  const int aNewState = !myActiveProgram.IsNull() ? GL_UPPER_LEFT : GL_LOWER_LEFT;
+  if (myPointSpriteOrig != aNewState)
+  {
+    myPointSpriteOrig = aNewState;
+    core15fwd->glPointParameteri (GL_POINT_SPRITE_COORD_ORIGIN, aNewState);
+  }
+#endif
+}
+
 // =======================================================================
 // function : SetGlNormalizeEnabled
 // purpose  :

src/OpenGl/OpenGl_Context.hxx

@@ -567,6 +567,12 @@ public: //! @name methods to alter or retrieve current state
   //! Setup point size.
   Standard_EXPORT void SetPointSize (const Standard_ShortReal theSize);
 
+  //! Setup point sprite origin using GL_POINT_SPRITE_COORD_ORIGIN state:
+  //! - GL_UPPER_LEFT when GLSL program is active;
+  //!   flipping should be handled in GLSL program for compatibility with OpenGL ES
+  //! - GL_LOWER_LEFT for FFP
+  Standard_EXPORT void SetPointSpriteOrigin();
+
   //! Setup texture matrix to active GLSL program or to FFP global state using glMatrixMode (GL_TEXTURE).
   Standard_EXPORT void SetTextureMatrix (const Handle(Graphic3d_TextureParams)& theParams);
 
@@ -716,6 +722,7 @@ private: //! @name fields tracking current state
   Handle(OpenGl_ShaderProgram) myActiveProgram;   //!< currently active GLSL program
   Handle(OpenGl_Sampler)       myTexSampler;      //!< currently active sampler object
   Handle(OpenGl_FrameBuffer)   myDefaultFbo;      //!< default Frame Buffer Object
+  Standard_Integer             myPointSpriteOrig; //!< GL_POINT_SPRITE_COORD_ORIGIN state (GL_UPPER_LEFT by default)
   Standard_Integer             myRenderMode;      //!< value for active rendering mode
   Standard_Integer             myReadBuffer;      //!< current read buffer
   Standard_Integer             myDrawBuffer;      //!< current draw buffer

src/OpenGl/OpenGl_PrimitiveArray.cxx

@@ -537,6 +537,7 @@ void OpenGl_PrimitiveArray::drawMarkers (const Handle(OpenGl_Workspace)& theWork
   {
     // Textured markers will be drawn with the point sprites
     aCtx->SetPointSize (anAspectMarker->MarkerSize());
+    aCtx->SetPointSpriteOrigin();
   #if !defined(GL_ES_VERSION_2_0)
     if (aCtx->core11 != NULL)
     {

src/OpenGl/OpenGl_ShaderManager.cxx

@@ -53,6 +53,9 @@ const char THE_VARY_TexCoord_Trsf[] =
   EOL"  aTex2.y = aCopy.x * aRotSin + aCopy.y * aRotCos;"
   EOL"  TexCoord = vec4(aTex2, occTexCoord.zw);";
 
+//! Auxiliary function to flip gl_PointCoord vertically
+#define THE_VEC2_glPointCoord "vec2 (gl_PointCoord.x, 1.0 - gl_PointCoord.y)"
+
 //! Auxiliary function to transform normal
 const char THE_FUNC_transformNormal[] =
   EOL"vec3 transformNormal (in vec3 theNormal)"
@@ -944,16 +947,18 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramFboBlit()
 // function : pointSpriteAlphaSrc
 // purpose  :
 // =======================================================================
-TCollection_AsciiString OpenGl_ShaderManager::pointSpriteAlphaSrc()
+TCollection_AsciiString OpenGl_ShaderManager::pointSpriteAlphaSrc (const Standard_Integer theBits)
 {
-  TCollection_AsciiString aSrcGetAlpha = EOL"float getAlpha(void) { return occTexture2D(occActiveSampler, gl_PointCoord).a; }";
+  TCollection_AsciiString aSrcGetAlpha = EOL"float getAlpha(void) { return occTexture2D(occActiveSampler, " THE_VEC2_glPointCoord ").a; }";
 #if !defined(GL_ES_VERSION_2_0)
-  if (myContext->core11 == NULL)
+  if (myContext->core11 == NULL
+   && (theBits & OpenGl_PO_TextureA) != 0)
   {
-    aSrcGetAlpha = EOL"float getAlpha(void) { return occTexture2D(occActiveSampler, gl_PointCoord).r; }";
+    aSrcGetAlpha = EOL"float getAlpha(void) { return occTexture2D(occActiveSampler, " THE_VEC2_glPointCoord ").r; }";
   }
+#else
+  (void )theBits;
 #endif
-
   return aSrcGetAlpha;
 }
 
@@ -988,30 +993,37 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramFlat (Handle(OpenGl_Shad
     aSrcVertExtraMain += EOL"  gl_PointSize = occPointSize;";
   #endif
 
-    if (textureUsed (theBits))
-    {
-      aSrcGetAlpha = pointSpriteAlphaSrc();
-
-      #if !defined(GL_ES_VERSION_2_0)
-        if (myContext->core11 != NULL
-         && myContext->IsGlGreaterEqual (2, 1))
-        {
-          aProgramSrc->SetHeader ("#version 120"); // gl_PointCoord has been added since GLSL 1.2
-        }
-      #endif
-    }
-
     if ((theBits & OpenGl_PO_TextureRGB) != 0)
     {
       aSrcFragGetColor =
-        EOL"vec4 getColor(void) { return occTexture2D(occActiveSampler, gl_PointCoord); }";
+        EOL"vec4 getColor(void) { return occTexture2D(occActiveSampler, " THE_VEC2_glPointCoord "); }";
     }
 
-    aSrcFragMainGetColor =
+    if (textureUsed (theBits))
-      EOL"  vec4 aColor = getColor();"
+    {
-      EOL"  aColor.a = getAlpha();"
+      aSrcGetAlpha = pointSpriteAlphaSrc (theBits);
-      EOL"  if (aColor.a <= 0.1) discard;"
+
-      EOL"  occFragColor = aColor;";
+    #if !defined(GL_ES_VERSION_2_0)
+      if (myContext->core11 != NULL
+        && myContext->IsGlGreaterEqual (2, 1))
+      {
+        aProgramSrc->SetHeader ("#version 120"); // gl_PointCoord has been added since GLSL 1.2
+      }
+    #endif
+
+      aSrcFragMainGetColor =
+        EOL"  vec4 aColor = getColor();"
+        EOL"  aColor.a = getAlpha();"
+        EOL"  if (aColor.a <= 0.1) discard;"
+        EOL"  occFragColor = aColor;";
+    }
+    else
+    {
+      aSrcFragMainGetColor =
+        EOL"  vec4 aColor = getColor();"
+        EOL"  if (aColor.a <= 0.1) discard;"
+        EOL"  occFragColor = aColor;";
+    }
   }
   else
   {
@@ -1162,7 +1174,7 @@ TCollection_AsciiString OpenGl_ShaderManager::pointSpriteShadingSrc (const TColl
   TCollection_AsciiString aSrcFragGetColor;
   if ((theBits & OpenGl_PO_TextureA) != 0)
   {
-    aSrcFragGetColor = pointSpriteAlphaSrc() +
+    aSrcFragGetColor = pointSpriteAlphaSrc (theBits) +
       EOL"vec4 getColor(void)"
       EOL"{"
       EOL"  vec4 aColor = " + theBaseColorSrc + ";"
@@ -1177,7 +1189,7 @@ TCollection_AsciiString OpenGl_ShaderManager::pointSpriteShadingSrc (const TColl
       EOL"vec4 getColor(void)"
       EOL"{"
       EOL"  vec4 aColor = " + theBaseColorSrc + ";"
-      EOL"  aColor = occTexture2D(occActiveSampler, gl_PointCoord) * aColor;"
+      EOL"  aColor = occTexture2D(occActiveSampler, " THE_VEC2_glPointCoord ") * aColor;"
       EOL"  if (aColor.a <= 0.1) discard;"
       EOL"  return aColor;"
       EOL"}";

src/OpenGl/OpenGl_ShaderManager.hxx

@@ -322,7 +322,7 @@ protected:
   }
 
   //! Prepare standard GLSL program for accessing point sprite alpha.
-  Standard_EXPORT TCollection_AsciiString pointSpriteAlphaSrc();
+  Standard_EXPORT TCollection_AsciiString pointSpriteAlphaSrc (const Standard_Integer theBits);
 
   //! Prepare standard GLSL program for computing point sprite shading.
   Standard_EXPORT TCollection_AsciiString pointSpriteShadingSrc (const TCollection_AsciiString theBaseColorSrc, const Standard_Integer theBits);

src/OpenGl/OpenGl_Workspace.cxx

@@ -411,7 +411,6 @@ void OpenGl_Workspace::setTextureParams (Handle(OpenGl_Texture)&
           glEnable  (GL_POINT_SPRITE);
           glTexEnvi (GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE);
           anEnvMode = GL_REPLACE;
-          myGlContext->core15->glPointParameteri (GL_POINT_SPRITE_COORD_ORIGIN, GL_LOWER_LEFT);
         }
         break;
       }

tests/bugs/vis/bug23654_MarkersRecompute

@@ -2,76 +2,22 @@ puts "========"
 puts "OCC23654 Markers recompute"
 puts "========"
 
-# reflects Aspect_TypeOfMarker enumeration
+pload VISUALIZATION
-set aMarkerTypeNames {
-  Aspect_TOM_POINT
-  Aspect_TOM_PLUS
-  Aspect_TOM_STAR
-  Aspect_TOM_X
-  Aspect_TOM_O
-  Aspect_TOM_O_POINT
-  Aspect_TOM_O_PLUS
-  Aspect_TOM_O_STAR
-  Aspect_TOM_O_X
-  Aspect_TOM_RING1
-  Aspect_TOM_RING2
-  Aspect_TOM_RING3
-  Aspect_TOM_BALL
-  Aspect_TOM_USERDEFINED
-}
-
-# custom marker
-set aCustom1 [locate_data_file images/marker_box1.png]
-set aCustom2 [locate_data_file images/marker_box2.png]
-set aCustom3 [locate_data_file images/marker_dot.png]
-
-# draw box in advance which should fit all our markers
-box b -8 -8 0 16 16 2
-
 vcaps -sprites
-set aV "Driver1/Viewer1/View1"
+source $env(CSF_OCCTSamplesPath)/tcl/markers.tcl
-vinit name=$aV l=32 t=32 w=512 h=512
-vactivate $aV
-vclear
-
-vbottom
-vdisplay b
-vfit
-verase b
-
-vfont add [locate_data_file DejaVuSans.ttf] SansFont
-
-for { set aMarkerType 0 } { $aMarkerType <= 13 } { incr aMarkerType } {
-  set aRow [expr $aMarkerType - 7]
-  set aCol 5
-  set aName [lindex $aMarkerTypeNames $aMarkerType]
-  vdrawtext "$aName" "$aName" -pos 0 [expr $aRow + 0.5] 0 -color 0.5 1.0 1.0 -halign center -valign center -angle 000 -zoom 0 -height 12 -aspect bold -font SansFont
-  if { $aMarkerType == 13 } {
-    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom1
-    set aCol [expr $aCol - 1]
-    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom2
-    set aCol [expr $aCol - 1]
-    vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom3
-  } else {
-    for { set aMarkerScale 1.0 } { $aMarkerScale <= 7 } { set aMarkerScale [expr $aMarkerScale + 0.5] } {
-      vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 MarkerType=$aMarkerType Scale=$aMarkerScale PointsOnSide=1
-      set aCol [expr $aCol - 1]
-    }
-  }
-}
 
 set anImage1 $imagedir/${casename}_1.png
 set anImage2 $imagedir/${casename}_2.png
 
 vdump $anImage1
 
-vclose $aV 1
+vclose Driver1/Viewer1/View1 1
 
-vinit name=$aV l=32 t=32 w=512 h=512
+vinit name=View1 l=32 t=32 w=512 h=512
-vactivate $aV
+vactivate Driver1/Viewer1/View1
 vbottom
-vdisplay b
+vdisplay -noupdate b
 vfit
-verase b
+vremove b
 
-vdump $anImage2
+vdump $anImage2

tests/bugs/vis/bug24131_markers

@@ -1,67 +0,0 @@
-puts "========"
-puts "OCC24131 Markers using Point Sprites"
-puts "========"
-
-# reflects Aspect_TypeOfMarker enumeration
-set aMarkerTypeNames {
-  Aspect_TOM_POINT
-  Aspect_TOM_PLUS
-  Aspect_TOM_STAR
-  Aspect_TOM_X
-  Aspect_TOM_O
-  Aspect_TOM_O_POINT
-  Aspect_TOM_O_PLUS
-  Aspect_TOM_O_STAR
-  Aspect_TOM_O_X
-  Aspect_TOM_RING1
-  Aspect_TOM_RING2
-  Aspect_TOM_RING3
-  Aspect_TOM_BALL
-  Aspect_TOM_USERDEFINED
-}
-
-
-# custom marker
-set aCustom1 [locate_data_file images/marker_box1.png]
-set aCustom2 [locate_data_file images/marker_box2.png]
-set aCustom3 [locate_data_file images/marker_dot.png]
-
-vfont add [locate_data_file DejaVuSans.ttf] SansFont
-
-# draw box in advance which should fit all our markers
-box b -8 -8 0 16 16 2
-puts "hI"
-for { set aMode 0 } { $aMode <= 1 } { incr aMode } {
-  set aTitle "bitmaps"
-  if { $aMode == 1 } { set aTitle "sprites" }
-  vcaps -sprites $aMode
-  set aV "Driver${aMode}/Viewer1/View1"
-  vinit name=$aV l=32 t=32 w=512 h=512
-  vactivate $aV
-  vclear
-
-  vbottom
-  vdisplay b
-  vfit
-  verase b
-
-  for { set aMarkerType 0 } { $aMarkerType <= 13 } { incr aMarkerType } {
-    set aRow [expr $aMarkerType - 7]
-    set aCol 5
-    set aName [lindex $aMarkerTypeNames $aMarkerType]
-    vdrawtext "$aName" "$aName" -pos 0 [expr $aRow + 0.5] 0 -color 0.5 1.0 1.0 -halign center -valign center -angle 000 -zoom 0 -height 12 -aspect bold -font SansFont
-    if { $aMarkerType == 13 } {
-      vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom1
-      set aCol [expr $aCol - 1]
-      vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom2
-      set aCol [expr $aCol - 1]
-      vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 PointsOnSide=1 FileName=$aCustom3
-    } else {
-      for { set aMarkerScale 1.0 } { $aMarkerScale <= 7 } { set aMarkerScale [expr $aMarkerScale + 0.5] } {
-        vmarkerstest m${aMarkerType}_${aCol} $aCol $aRow 0 MarkerType=$aMarkerType Scale=$aMarkerScale PointsOnSide=1
-        set aCol [expr $aCol - 1]
-      }
-    }
-  }
-  vdump $imagedir/${casename}_${aTitle}.png
-}

tests/bugs/vis/bug24131_markers_bitmap

@@ -0,0 +1,8 @@
+puts "========"
+puts "OCC24131 Markers using deprecated glBitmap"
+puts "========"
+
+pload VISUALIZATION
+vcaps -sprites 0 -ffp 1
+source $env(CSF_OCCTSamplesPath)/tcl/markers.tcl
+vdump $imagedir/${casename}.png

tests/bugs/vis/bug24131_markers_core

@@ -0,0 +1,8 @@
+puts "========"
+puts "OCC24131 Markers using GLSL programs in Core Profile"
+puts "========"
+
+pload VISUALIZATION
+vcaps -core
+source $env(CSF_OCCTSamplesPath)/tcl/markers.tcl
+vdump $imagedir/${casename}.png

tests/bugs/vis/bug24131_markers_glsl

@@ -0,0 +1,8 @@
+puts "========"
+puts "OCC24131 Markers using GLSL programs in Compatible Profile"
+puts "========"
+
+pload VISUALIZATION
+vcaps -compatibleProfile -sprites 1 -ffp 0
+source $env(CSF_OCCTSamplesPath)/tcl/markers.tcl
+vdump $imagedir/${casename}.png

tests/bugs/vis/bug24131_markers_sprites

@@ -0,0 +1,8 @@
+puts "========"
+puts "OCC24131 Markers using Point Sprites and FFP"
+puts "========"
+
+pload VISUALIZATION
+vcaps -sprites 1 -ffp 1
+source $env(CSF_OCCTSamplesPath)/tcl/markers.tcl
+vdump $imagedir/${casename}.png