-Fixed issue with color ramp shader and doubles

ersts · ersts · commit 8349cfd92306 · 2009-03-11T22:32:49.000Z
-Closes ticket #1497 git-svn-id: http://svn.osgeo.org/qgis/trunk@10271 c8812cc2-4d05-0410-92ff-de0c093fc19c
diff --git a/src/core/raster/qgscolorrampshader.cpp b/src/core/raster/qgscolorrampshader.cpp
@@ -17,11 +17,14 @@ originally part of the larger QgsRasterLayer class
  *   (at your option) any later version.                                   *
  *                                                                         *
  ***************************************************************************/
+#define REALLY_SMALL 0.0000001
 
 #include "qgslogger.h"
 
 #include "qgscolorrampshader.h"
 
+#include <math.h>
+
 QgsColorRampShader::QgsColorRampShader( double theMinimumValue, double theMaximumValue ) : QgsRasterShaderFunction( theMinimumValue, theMaximumValue )
 {
   QgsDebugMsg( "called." );
@@ -54,17 +57,19 @@ bool QgsColorRampShader::discreteColor( double theValue, int* theReturnRedValue,
     return false;
   }
 
+  double myTinyDiff = 0.0;
   QgsColorRampShader::ColorRampItem myColorRampItem;
   while ( mCurrentColorRampItemIndex >= 0 && mCurrentColorRampItemIndex < myColorRampItemCount )
   {
     //Start searching from the last index - assumtion is that neighboring pixels tend to be similar values
     myColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex );
+    myTinyDiff = fabs( theValue - myColorRampItem.value );
     //If the previous entry is less, then search closer to the top of the list (assumes mColorRampItemList is sorted)
     if ( mCurrentColorRampItemIndex != 0 && theValue <= mColorRampItemList.at( mCurrentColorRampItemIndex - 1 ).value )
     {
       mCurrentColorRampItemIndex--;
     }
-    else if ( theValue <= myColorRampItem.value )
+    else if ( theValue <= myColorRampItem.value || myTinyDiff <= REALLY_SMALL )
     {
       *theReturnRedValue = myColorRampItem.color.red();
       *theReturnGreenValue = myColorRampItem.color.green();
@@ -94,12 +99,14 @@ bool QgsColorRampShader::exactColor( double theValue, int* theReturnRedValue, in
     return false;
   }
 
+  double myTinyDiff = 0.0;
   QgsColorRampShader::ColorRampItem myColorRampItem;
   while ( mCurrentColorRampItemIndex >= 0 && mCurrentColorRampItemIndex < myColorRampItemCount )
   {
     //Start searching from the last index - assumtion is that neighboring pixels tend to be similar values
     myColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex );
-    if ( theValue == myColorRampItem.value )
+    myTinyDiff = fabs( theValue - myColorRampItem.value );
+    if ( theValue == myColorRampItem.value || myTinyDiff <= REALLY_SMALL )
     {
       *theReturnRedValue = myColorRampItem.color.red();
       *theReturnGreenValue = myColorRampItem.color.green();
@@ -133,26 +140,27 @@ bool QgsColorRampShader::exactColor( double theValue, int* theReturnRedValue, in
 
 bool QgsColorRampShader::interpolatedColor( double theValue, int* theReturnRedValue, int* theReturnGreenValue, int* theReturnBlueValue )
 {
-
   int myColorRampItemCount = mColorRampItemList.count();
   if ( myColorRampItemCount <= 0 )
   {
     return false;
   }
 
+  double myTinyDiff = 0.0;
   double myCurrentRampRange; //difference between two consecutive entry values
   double myOffsetInRange; //difference between the previous entry value and value
   QgsColorRampShader::ColorRampItem myColorRampItem;
   while ( mCurrentColorRampItemIndex >= 0 && mCurrentColorRampItemIndex < myColorRampItemCount )
   {
     //Start searching from the last index - assumtion is that neighboring pixels tend to be similar values
     myColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex );
+    myTinyDiff = fabs( theValue - myColorRampItem.value );
     //If the previous entry is less, then search closer to the top of the list (assumes mColorRampItemList is sorted)
     if ( mCurrentColorRampItemIndex != 0 && theValue <= mColorRampItemList.at( mCurrentColorRampItemIndex - 1 ).value )
     {
       mCurrentColorRampItemIndex--;
     }
-    else if ( mCurrentColorRampItemIndex != 0 && theValue <= myColorRampItem.value )
+    else if ( mCurrentColorRampItemIndex != 0 && ( theValue <= myColorRampItem.value || myTinyDiff <= REALLY_SMALL ) )
     {
       QgsColorRampShader::ColorRampItem myPreviousColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex - 1 );
       myCurrentRampRange = myColorRampItem.value - myPreviousColorRampItem.value;

Original file line number	Diff line number	Diff line change
`@@ -17,11 +17,14 @@ originally part of the larger QgsRasterLayer class`
`17`	`17`	`* (at your option) any later version. *`
`18`	`18`	`* *`
`19`	`19`	`***************************************************************************/`
	`20`	`+#define REALLY_SMALL 0.0000001`
`20`	`21`
`21`	`22`	`#include "qgslogger.h"`
`22`	`23`
`23`	`24`	`#include "qgscolorrampshader.h"`
`24`	`25`
	`26`	`+#include <math.h>`
	`27`	`+`
`25`	`28`	`QgsColorRampShader::QgsColorRampShader( double theMinimumValue, double theMaximumValue ) : QgsRasterShaderFunction( theMinimumValue, theMaximumValue )`
`26`	`29`	`{`
`27`	`30`	`QgsDebugMsg( "called." );`
`@@ -54,17 +57,19 @@ bool QgsColorRampShader::discreteColor( double theValue, int* theReturnRedValue,`
`54`	`57`	`return false;`
`55`	`58`	`}`
`56`	`59`
	`60`	`+ double myTinyDiff = 0.0;`
`57`	`61`	`QgsColorRampShader::ColorRampItem myColorRampItem;`
`58`	`62`	`while ( mCurrentColorRampItemIndex >= 0 && mCurrentColorRampItemIndex < myColorRampItemCount )`
`59`	`63`	`{`
`60`	`64`	`//Start searching from the last index - assumtion is that neighboring pixels tend to be similar values`
`61`	`65`	`myColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex );`
	`66`	`+ myTinyDiff = fabs( theValue - myColorRampItem.value );`
`62`	`67`	`//If the previous entry is less, then search closer to the top of the list (assumes mColorRampItemList is sorted)`
`63`	`68`	`if ( mCurrentColorRampItemIndex != 0 && theValue <= mColorRampItemList.at( mCurrentColorRampItemIndex - 1 ).value )`
`64`	`69`	`{`
`65`	`70`	`mCurrentColorRampItemIndex--;`
`66`	`71`	`}`
`67`		`- else if ( theValue <= myColorRampItem.value )`
	`72`	`+ else if ( theValue <= myColorRampItem.value \|\| myTinyDiff <= REALLY_SMALL )`
`68`	`73`	`{`
`69`	`74`	`*theReturnRedValue = myColorRampItem.color.red();`
`70`	`75`	`*theReturnGreenValue = myColorRampItem.color.green();`
`@@ -94,12 +99,14 @@ bool QgsColorRampShader::exactColor( double theValue, int* theReturnRedValue, in`
`94`	`99`	`return false;`
`95`	`100`	`}`
`96`	`101`
	`102`	`+ double myTinyDiff = 0.0;`
`97`	`103`	`QgsColorRampShader::ColorRampItem myColorRampItem;`
`98`	`104`	`while ( mCurrentColorRampItemIndex >= 0 && mCurrentColorRampItemIndex < myColorRampItemCount )`
`99`	`105`	`{`
`100`	`106`	`//Start searching from the last index - assumtion is that neighboring pixels tend to be similar values`
`101`	`107`	`myColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex );`
`102`		`- if ( theValue == myColorRampItem.value )`
	`108`	`+ myTinyDiff = fabs( theValue - myColorRampItem.value );`
	`109`	`+ if ( theValue == myColorRampItem.value \|\| myTinyDiff <= REALLY_SMALL )`
`103`	`110`	`{`
`104`	`111`	`*theReturnRedValue = myColorRampItem.color.red();`
`105`	`112`	`*theReturnGreenValue = myColorRampItem.color.green();`
`@@ -133,26 +140,27 @@ bool QgsColorRampShader::exactColor( double theValue, int* theReturnRedValue, in`
`133`	`140`
`134`	`141`	`bool QgsColorRampShader::interpolatedColor( double theValue, int* theReturnRedValue, int* theReturnGreenValue, int* theReturnBlueValue )`
`135`	`142`	`{`
`136`		`-`
`137`	`143`	`int myColorRampItemCount = mColorRampItemList.count();`
`138`	`144`	`if ( myColorRampItemCount <= 0 )`
`139`	`145`	`{`
`140`	`146`	`return false;`
`141`	`147`	`}`
`142`	`148`
	`149`	`+ double myTinyDiff = 0.0;`
`143`	`150`	`double myCurrentRampRange; //difference between two consecutive entry values`
`144`	`151`	`double myOffsetInRange; //difference between the previous entry value and value`
`145`	`152`	`QgsColorRampShader::ColorRampItem myColorRampItem;`
`146`	`153`	`while ( mCurrentColorRampItemIndex >= 0 && mCurrentColorRampItemIndex < myColorRampItemCount )`
`147`	`154`	`{`
`148`	`155`	`//Start searching from the last index - assumtion is that neighboring pixels tend to be similar values`
`149`	`156`	`myColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex );`
	`157`	`+ myTinyDiff = fabs( theValue - myColorRampItem.value );`
`150`	`158`	`//If the previous entry is less, then search closer to the top of the list (assumes mColorRampItemList is sorted)`
`151`	`159`	`if ( mCurrentColorRampItemIndex != 0 && theValue <= mColorRampItemList.at( mCurrentColorRampItemIndex - 1 ).value )`
`152`	`160`	`{`
`153`	`161`	`mCurrentColorRampItemIndex--;`
`154`	`162`	`}`
`155`		`- else if ( mCurrentColorRampItemIndex != 0 && theValue <= myColorRampItem.value )`
	`163`	`+ else if ( mCurrentColorRampItemIndex != 0 && ( theValue <= myColorRampItem.value \|\| myTinyDiff <= REALLY_SMALL ) )`
`156`	`164`	`{`
`157`	`165`	`QgsColorRampShader::ColorRampItem myPreviousColorRampItem = mColorRampItemList.value( mCurrentColorRampItemIndex - 1 );`
`158`	`166`	`myCurrentRampRange = myColorRampItem.value - myPreviousColorRampItem.value;`