From 6f26baa0fcf640f1829f984ec9e5e6907561af59 Mon Sep 17 00:00:00 2001
From: kgv <kgv@opencascade.com>
Date: Fri, 20 Jul 2018 10:40:14 +0300
Subject: [PATCH] 0029975: Visualization - Graphic3d_ClipPlane::ProbeBox()
 returns Out for fully In box

---
 src/Graphic3d/Graphic3d_ClipPlane.hxx | 46 ++++++++-------------------
 tests/v3d/glsl/clipping1              |  4 +++
 2 files changed, 18 insertions(+), 32 deletions(-)

diff --git a/src/Graphic3d/Graphic3d_ClipPlane.hxx b/src/Graphic3d/Graphic3d_ClipPlane.hxx
index 388ae39b4d..b1857607e1 100755
--- a/src/Graphic3d/Graphic3d_ClipPlane.hxx
+++ b/src/Graphic3d/Graphic3d_ClipPlane.hxx
@@ -255,58 +255,40 @@ public:
   //! Check if the given point is outside / inside / on section.
   Graphic3d_ClipState ProbePoint (const Graphic3d_Vec4d& thePoint) const
   {
+    Graphic3d_ClipState aState = Graphic3d_ClipState_Out;
     for (const Graphic3d_ClipPlane* aPlaneIter = this; aPlaneIter != NULL; aPlaneIter = aPlaneIter->myNextInChain.get())
     {
       Graphic3d_ClipState aPlnState = aPlaneIter->ProbePointHalfspace (thePoint);
-      if (aPlnState == Graphic3d_ClipState_On)
+      if (aPlnState == Graphic3d_ClipState_In)
       {
-        return Graphic3d_ClipState_On;
+        return Graphic3d_ClipState_In;
       }
-      else if (aPlnState == Graphic3d_ClipState_Out
-            && aPlaneIter->myNextInChain.IsNull())
+      else if (aPlnState != Graphic3d_ClipState_Out)
       {
-        return Graphic3d_ClipState_Out;
+        aState = Graphic3d_ClipState_On;
       }
     }
-    return Graphic3d_ClipState_In;
+    return aState;
   }
 
   //! Check if the given bounding box is fully outside / fully inside.
   Graphic3d_ClipState ProbeBox (const Graphic3d_BndBox3d& theBox) const
   {
-    Graphic3d_ClipState aPrevState = Graphic3d_ClipState_On;
+    Graphic3d_ClipState aState = Graphic3d_ClipState_Out;
     for (const Graphic3d_ClipPlane* aPlaneIter = this; aPlaneIter != NULL; aPlaneIter = aPlaneIter->myNextInChain.get())
     {
-      if (aPlaneIter->IsBoxFullOutHalfspace (theBox))
+      if (aPlaneIter->IsBoxFullInHalfspace (theBox))
       {
-        if (aPlaneIter->myNextInChain.IsNull())
-        {
-          return Graphic3d_ClipState_Out;
-        }
-        else if (aPrevState == Graphic3d_ClipState_In)
-        {
-          return Graphic3d_ClipState_On;
-        }
-        aPrevState = Graphic3d_ClipState_Out;
+        // within union operation, if box is entirely inside at least one half-space, others can be ignored
+        return Graphic3d_ClipState_In;
       }
-      else if (aPlaneIter->IsBoxFullInHalfspace (theBox))
+      else if (!aPlaneIter->IsBoxFullOutHalfspace (theBox))
       {
-        if (aPlaneIter->myNextInChain.IsNull())
-        {
-          return Graphic3d_ClipState_In;
-        }
-        else if (aPrevState == Graphic3d_ClipState_Out)
-        {
-          return Graphic3d_ClipState_On;
-        }
-        aPrevState = Graphic3d_ClipState_In;
-      }
-      else
-      {
-        return Graphic3d_ClipState_On;
+        // if at least one full out test fail, clipping state is inconclusive (partially clipped)
+        aState = Graphic3d_ClipState_On;
       }
     }
-    return Graphic3d_ClipState_On;
+    return aState;
   }
 
 public:
diff --git a/tests/v3d/glsl/clipping1 b/tests/v3d/glsl/clipping1
index 126b99b85d..271a73a94a 100644
--- a/tests/v3d/glsl/clipping1
+++ b/tests/v3d/glsl/clipping1
@@ -19,6 +19,7 @@ box b2 20 40 0 20 10 70
 box b3 0  40 0 20 10 70
 box b4 0  10 0 10 30 70
 box b5 0   0 0 30 10 70
+box bb 10 -10 0 20 10 10
 
 set aNbParts 6
 set aColors { RED YELLOW GREEN GRAY MAGENTA1 ORANGE }
@@ -32,6 +33,8 @@ vinit name=View1 w=512 h=512
 vviewparams -scale 4.66737 -proj 0.465292 -0.577133 0.671134 -up -0.46873 0.482524 0.739907 -at 15.807 37.1157 21.9799
 
 vpoint p0 0 0 0
+vdisplay -dispMode 1 bb
+vaspects -noupdate bb -setColor CYAN1
 vzbufftrihedron
 
 puts "Display the geometry as dedicated objects"
@@ -74,6 +77,7 @@ vfit
 vdisplay pp1 pp2
 
 vclipplane pln -set {*}$aCapParams -equation1 0 0 -1 40 -equation2  0 1 0 -15
+if { [vreadpixel 200 360 rgb name] != "DARKTURQUOISE" } { puts "Error: bb should NOT be clipped" }
 vdump $::imagedir/${::casename}_2.png
 
 vclipplane pln -set {*}$aCapParams -equation1 0 0 -1 40 -equation2  0 1 0 -15 -equation3 -1 0 0 5