gml_Geometry.h

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00001 /**
00002  * @file gml_Geometry.h
00003  *
00004  *  Structures to represent 2D points and rectangles.
00005  *
00006  * Copyright (c) 2003 CLIPS-IMAG
00007  *
00008  * See the file "gml_LicenseTerms.txt" for information on usage and redistribution
00009  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
00010  *
00011  *  Created on Sept. 20, 2003 (FB).
00012  */
00013 #ifndef __GML_GEOMETRY__
00014 #define __GML_GEOMETRY__
00015 
00016 #include <assert.h>
00017 
00018 #include "gml/base/gml_Types.h"
00019 #include "gml/math/gml_Math.h"
00020 
00021 
00022 
00023 
00024 /**
00025  * gml_TRect --
00026  *
00027  *    2D rectangles with integer coordinates.
00028  */
00029 typedef struct
00030 {
00031   SInt32    fLeft;
00032   SInt32    fTop;
00033   SInt32    fRight;
00034   SInt32    fBottom;
00035 
00036 } gml_TRect;
00037 
00038 
00039 
00040 /**
00041  * gml_TPoint --
00042  *    2D points with integer coordinates.
00043  */
00044 typedef struct
00045 {
00046   SInt32    fX;
00047   SInt32    fY;
00048   
00049 } gml_TPoint;
00050 
00051 
00052 
00053 /**
00054  * gml_TRectFloat --
00055  *
00056  *    2D rectangles with floating-point coordinates.
00057  */
00058 typedef struct
00059 {
00060   Float32    fLeft;
00061   Float32    fTop;
00062   Float32    fRight;
00063   Float32    fBottom;
00064 
00065 } gml_TRectFloat;
00066 
00067 
00068 
00069 /**
00070  * gml_TPointFloat --
00071  *
00072  *    2D points with floating-point coordinates.
00073  */
00074 typedef struct
00075 {
00076   Float32    fX;
00077   Float32    fY;
00078   
00079 } gml_TPointFloat;
00080 
00081 
00082 
00083 /**
00084  * gml_Rect_Width --
00085  *
00086  *    Return the width of a gml_TRect.
00087  */
00088 inline static
00089 SInt32 gml_Rect_Width (gml_TRect* rect)
00090 {
00091   return rect->fRight - rect->fLeft;
00092 }
00093 
00094 
00095 
00096 /**
00097  * gml_Rect_Height --
00098  *
00099  *    Return the height of a gml_TRect.
00100  */
00101 inline static
00102 SInt32 gml_Rect_Height (gml_TRect* rect)
00103 {
00104   return rect->fBottom - rect->fTop;
00105 }
00106 
00107 
00108 /**
00109  * gml_Rect_Equal --
00110  *
00111  *    Return true iff the two rectangles are identical.
00112  */
00113 inline static
00114 gml_TBoolean gml_Rect_Equal (gml_TRect* rect0, gml_TRect* rect1)
00115 {
00116   return (rect0->fLeft == rect1->fLeft &&
00117           rect0->fRight == rect1->fRight &&
00118           rect0->fTop == rect1->fTop &&
00119           rect0->fBottom == rect1->fBottom) ? gml_cTrue : gml_cFalse;
00120 }
00121 
00122 
00123 /**
00124  * gml_SetValidRect --
00125  *
00126  *   If <rectPtr> is NULL, set <validRect> to the (0, 0, w, h) rectangle.
00127  *   Else set it to the intersection of that rectangle and the rectangle 
00128  *   pointed by <rectPtr>.
00129  */
00130 inline static
00131 void gml_SetValidRect (SInt32 w, SInt32 h, gml_TRect* rectPtr, gml_TRect* validRect)
00132 {  
00133   assert (validRect != NULL);
00134   
00135   if (rectPtr == NULL) {
00136     validRect->fLeft   = 0;
00137     validRect->fTop    = 0;
00138     validRect->fRight  = w;
00139     validRect->fBottom = h;
00140   } else {
00141     validRect->fLeft   = Min (Max (rectPtr->fLeft, SInt32(0)), w);
00142     validRect->fRight  = Max (Min (rectPtr->fRight, w), validRect->fLeft);
00143     validRect->fTop    = Min (Max (rectPtr->fTop, SInt32(0)), h);
00144     validRect->fBottom = Max (Min (rectPtr->fBottom, h), validRect->fTop);
00145   }
00146 }
00147 
00148 
00149 #endif /* ifndef __GML_GEOMETRY__ */
00150