code easier to understand

eeschema/class_libentry.cpp

@@ -1168,6 +1168,18 @@ void LIB_COMPONENT::MirrorSelectedItemsH( const wxPoint& center )
 }
 
 
+
+/**
+ * Locate a draw object.
+ *
+ * @param unit - Unit number of draw item.
+ * @param convert - Body style of draw item.
+ * @param type - Draw object type, set to 0 to search for any type.
+ * @param pt - Coordinate for hit testing.
+ *
+ * @return LIB_DRAW_ITEM - Pointer the the draw object if found.
+ *                         Otherwise NULL.
+ */
 LIB_DRAW_ITEM* LIB_COMPONENT::LocateDrawItem( int unit, int convert,
                                               KICAD_T type, const wxPoint& pt )
 {
@@ -1201,6 +1213,46 @@ LIB_DRAW_ITEM* LIB_COMPONENT::LocateDrawItem( int unit, int convert,
     return NULL;
 }
 
+/** Function HitTest (overlaid)
+ * @return true if the point aPosRef is near this object
+ * @param aPosRef = a wxPoint to test
+ * @param aThreshold = max distance to this object (usually the half
+ *                     thickness of a line)
+ * @param aTransMat = the transform matrix
+ *
+ * @return LIB_DRAW_ITEM - Pointer the the draw object if found.
+ *                         Otherwise NULL.
+ */
+LIB_DRAW_ITEM* LIB_COMPONENT::LocateDrawItem( int unit, int convert,
+                                              KICAD_T type, const wxPoint& pt, const int aTransMat[2][2] )
+{
+    /* we use LocateDrawItem( int unit, int convert, KICAD_T type, const wxPoint& pt )
+     * to search items.
+     * because this function uses DefaultTransformMatrix as orient/mirror matrix
+     * we temporary copy aTransMat in DefaultTransformMatrix
+    */
+    LIB_DRAW_ITEM * item;
+    int matrix[2][2];
+    for ( int ii =0; ii<2;ii++ )
+    {
+        for ( int jj =0; jj<2;jj++ )
+        {
+            matrix[ii][jj] = aTransMat[ii][jj];
+            EXCHG(matrix[ii][jj], DefaultTransformMatrix[ii][jj]);
+        }
+    }
+    item = LocateDrawItem( unit, convert, type, pt );
+    //Restore matrix
+    for ( int ii =0; ii<2;ii++ )
+    {
+        for ( int jj =0; jj<2;jj++ )
+        {
+            EXCHG(matrix[ii][jj], DefaultTransformMatrix[ii][jj]);
+        }
+    }
+    
+    return item;
+}
 
 void LIB_COMPONENT::SetPartCount( int count )
 {

eeschema/class_libentry.h

@@ -356,6 +356,21 @@ public:
     LIB_DRAW_ITEM* LocateDrawItem( int unit, int convert, KICAD_T type,
                                    const wxPoint& pt );
 
+    /**
+     * Locate a draw object (overlaid)
+     *
+     * @param unit - Unit number of draw item.
+     * @param convert - Body style of draw item.
+     * @param type - Draw object type, set to 0 to search for any type.
+     * @param pt - Coordinate for hit testing.
+     * @param aTransMat = the transform matrix
+     *
+     * @return LIB_DRAW_ITEM - Pointer the the draw object if found.
+     *                         Otherwise NULL.
+     */
+    LIB_DRAW_ITEM* LocateDrawItem( int unit, int convert, KICAD_T type,
+                                   const wxPoint& pt, const int aTransMat[2][2] );
+
     /**
      * Return a reference to the draw item list.
      *

eeschema/locate.cpp

@@ -686,38 +686,6 @@ Hierarchical_PIN_Sheet_Struct* LocateSheetLabel( DrawSheetStruct* Sheet,
     return NULL;
 }
 
-/* helper function used to locate graphics items in a lib component (in library space)
- * to a given location given in schematic space
- * in schematic space, a component is an image of the lib component, rotated and mirorred
- * by its mirror/rotation matrix
- * this function calculates the invert matrix of the mirror/rotation matrix
- * it is used to calculate the position in in library space from
- * the position in schematic space of a test point, corresponding to a given component 
- */
-bool InvertMatrix(int aSource[2][2], int aDest[2][2] )
-{
-    /* for a source matrix (a,b, c,d) a, if the first line, and cd the second line
-    * the invert matrix is 1/det * comatrix
-    * det = ad-bc
-    * comatrix = (d,-b, -c,a)
-    * a = aSource[0][0]
-    * b = aSource[0][1]
-    * c = aSource[1][0]
-    * d = aSource[1][1]
-    * in eeschema, values are 1, 0 or -1 only and we can use integers only
-    */
-    bool success = true;
-    int det = aSource[0][0]*aSource[1][1] - aSource[0][1]*aSource[1][0];
-    wxASSERT(det);
-    if( det == 0 )  // Should not occur with eeschema matrix transform
-        det = 1;
-    aDest[0][0] = aSource[1][1]/det;
-    aDest[0][1] = -aSource[0][1]/det;
-    aDest[1][0] = -aSource[1][0]/det;
-    aDest[1][1] = aSource[0][0]/det;
-
-    return success;
-}
 
 LibDrawPin* LocateAnyPin( SCH_ITEM* DrawList, const wxPoint& RefPos,
                           SCH_COMPONENT** libpart )
@@ -738,24 +706,14 @@ LibDrawPin* LocateAnyPin( SCH_ITEM* DrawList, const wxPoint& RefPos,
         if( Entry == NULL )
             continue;
         /* we use LocateDrawItem to locate pns. but this function suppose a component 
-         * at 0,0 location, in normal orientation/mirror
-         * So we must calculate the ref position in component space
+         * at 0,0 location
+         * So we must calculate the ref position relative to the component
         */
-        // Calculate the position relative to the component (in library space the component is at location 0,0)
         wxPoint libPos = RefPos - schItem->m_Pos;
-        // Calculate the equivalent position of the test point for a normal orient component
-        int itransMat[2][2];
-        InvertMatrix(schItem->m_Transform, itransMat );
-        libPos = TransformCoordinate(itransMat, libPos);
-        // LocateDrawItem uses DefaultTransformMatrix as matrix orientation of the component
-        // so we must recalculate libPos for this orientation before calling LocateDrawItem
-        InvertMatrix(DefaultTransformMatrix, itransMat );
-        libPos = TransformCoordinate(itransMat, libPos);
-        wxPoint schPos = TransformCoordinate(schItem->m_Transform, libPos);
         Pin = (LibDrawPin*) Entry->LocateDrawItem( schItem->m_Multi,
                                                    schItem->m_Convert,
                                                    COMPONENT_PIN_DRAW_TYPE,
-                                                   libPos );
+                                                   libPos, schItem->m_Transform );
         if( Pin )
             break;
     }