Fix incorrect calculation of raster layer units per pixel x/y

nyalldawson · nyalldawson · commit 2e7990f19c7f · 2018-04-06T14:19:09.000+10:00
(cherry-picked from cd052d3)
diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
@@ -557,7 +557,7 @@ double QgsRasterLayer::rasterUnitsPerPixelX() const
 // We can only use one of the mGeoTransform[], so go with the
 // horisontal one.
 
-  if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && mDataProvider->xSize() > 0 )
+  if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && !qgsDoubleNear( mDataProvider->xSize(), 0.0 ) )
   {
     return mDataProvider->extent().width() / mDataProvider->xSize();
   }
@@ -566,7 +566,7 @@ double QgsRasterLayer::rasterUnitsPerPixelX() const
 
 double QgsRasterLayer::rasterUnitsPerPixelY() const
 {
-  if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && mDataProvider->xSize() > 0 )
+  if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && !qgsDoubleNear( mDataProvider->ySize(), 0.0 ) )
   {
     return mDataProvider->extent().height() / mDataProvider->ySize();
   }

Original file line number	Diff line number	Diff line change
`@@ -557,7 +557,7 @@ double QgsRasterLayer::rasterUnitsPerPixelX() const`
`557`	`557`	`// We can only use one of the mGeoTransform[], so go with the`
`558`	`558`	`// horisontal one.`
`559`	`559`
`560`		`- if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && mDataProvider->xSize() > 0 )`
	`560`	`+ if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && !qgsDoubleNear( mDataProvider->xSize(), 0.0 ) )`
`561`	`561`	`{`
`562`	`562`	`return mDataProvider->extent().width() / mDataProvider->xSize();`
`563`	`563`	`}`
`@@ -566,7 +566,7 @@ double QgsRasterLayer::rasterUnitsPerPixelX() const`
`566`	`566`
`567`	`567`	`double QgsRasterLayer::rasterUnitsPerPixelY() const`
`568`	`568`	`{`
`569`		`- if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && mDataProvider->xSize() > 0 )`
	`569`	`+ if ( mDataProvider->capabilities() & QgsRasterDataProvider::Size && !qgsDoubleNear( mDataProvider->ySize(), 0.0 ) )`
`570`	`570`	`{`
`571`	`571`	`return mDataProvider->extent().height() / mDataProvider->ySize();`
`572`	`572`	`}`