Merge pull request #2279 from sjchao/master

fixed #2030: Fixing a display bug when a scrollView nested in another scrollView. The parent's scissor rect need to be considered, when setting the scissor rect in the subScrollView.

cocos2dx/platform/CCEGLViewProtocol.cpp

@@ -154,17 +154,33 @@ void CCEGLViewProtocol::setScissorInPoints(float x , float y , float w , float h
               (GLsizei)(h * m_fScaleY));
 }
 
-void CCEGLViewProtocol::setViewName(const char* pszViewName)
-{
-    if (pszViewName != NULL && strlen(pszViewName) > 0)
-    {
-        strncpy(m_szViewName, pszViewName, sizeof(m_szViewName));
-    }
-}
-
-const char* CCEGLViewProtocol::getViewName()
-{
-    return m_szViewName;
+bool CCEGLViewProtocol::isScissorEnabled()
+{
+	return glIsEnabled(GL_SCISSOR_TEST);
+}
+
+CCRect CCEGLViewProtocol::getScissorRect()
+{
+	GLfloat params[4];
+	glGetFloatv(GL_SCISSOR_BOX, params);
+	float x = (params[0] - m_obViewPortRect.origin.x) / m_fScaleX;
+	float y = (params[1] - m_obViewPortRect.origin.y) / m_fScaleY;
+	float w = params[2] / m_fScaleX;
+	float h = params[3] / m_fScaleY;
+	return CCRectMake(x, y, w, h);
+}
+
+void CCEGLViewProtocol::setViewName(const char* pszViewName)
+{
+    if (pszViewName != NULL && strlen(pszViewName) > 0)
+    {
+        strncpy(m_szViewName, pszViewName, sizeof(m_szViewName));
+    }
+}
+
+const char* CCEGLViewProtocol::getViewName()
+{
+    return m_szViewName;
 }
 
 void CCEGLViewProtocol::handleTouchesBegin(int num, int ids[], float xs[], float ys[])

cocos2dx/platform/CCEGLViewProtocol.h

@@ -98,6 +98,16 @@ public:
      */
     virtual void setScissorInPoints(float x , float y , float w , float h);
 
+    /**
+     * Get whether GL_SCISSOR_TEST is enable
+     */
+    virtual bool isScissorEnabled();
+
+    /**
+     * Get the current scissor rectangle
+     */
+    virtual CCRect getScissorRect();
+
     virtual void setViewName(const char* pszViewName);
 
     const char* getViewName();

extensions/GUI/CCScrollView/CCScrollView.cpp

@@ -492,11 +492,24 @@ void CCScrollView::beforeDraw()
 {
     if (m_bClippingToBounds)
     {
-		CCRect frame = getViewRect();
-        
-        glEnable(GL_SCISSOR_TEST);
-        
-        CCEGLView::sharedOpenGLView()->setScissorInPoints(frame.origin.x, frame.origin.y, frame.size.width, frame.size.height);
+		m_bScissorRestored = false;
+        CCRect frame = getViewRect();
+        if (CCEGLView::sharedOpenGLView()->isScissorEnabled()) {
+            m_bScissorRestored = true;
+            m_tParentScissorRect = CCEGLView::sharedOpenGLView()->getScissorRect();
+            //set the intersection of m_tParentScissorRect and frame as the new scissor rect
+            if (frame.intersectsRect(m_tParentScissorRect)) {
+                float x = MAX(frame.origin.x, m_tParentScissorRect.origin.x);
+                float y = MAX(frame.origin.y, m_tParentScissorRect.origin.y);
+                float xx = MIN(frame.origin.x+frame.size.width, m_tParentScissorRect.origin.x+m_tParentScissorRect.size.width);
+                float yy = MIN(frame.origin.y+frame.size.height, m_tParentScissorRect.origin.y+m_tParentScissorRect.size.height);
+                CCEGLView::sharedOpenGLView()->setScissorInPoints(x, y, xx-x, yy-y);
+            }
+        }
+        else {
+            glEnable(GL_SCISSOR_TEST);
+            CCEGLView::sharedOpenGLView()->setScissorInPoints(frame.origin.x, frame.origin.y, frame.size.width, frame.size.height);
+        }
     }
 }
 
@@ -508,7 +521,12 @@ void CCScrollView::afterDraw()
 {
     if (m_bClippingToBounds)
     {
-        glDisable(GL_SCISSOR_TEST);
+        if (m_bScissorRestored) {//restore the parent's scissor rect
+            CCEGLView::sharedOpenGLView()->setScissorInPoints(m_tParentScissorRect.origin.x, m_tParentScissorRect.origin.y, m_tParentScissorRect.size.width, m_tParentScissorRect.size.height);
+        }
+        else {
+            glDisable(GL_SCISSOR_TEST);
+        }
     }
 }
 

extensions/GUI/CCScrollView/CCScrollView.h

@@ -317,6 +317,11 @@ protected:
      * max and min scale
      */
     float m_fMinScale, m_fMaxScale;
+    /**
+     * scissor rect for parent, just for restoring GL_SCISSOR_BOX
+     */
+    CCRect m_tParentScissorRect;
+    bool m_bScissorRestored;
 };
 
 // end of GUI group