use native GDAL functions

python/plugins/processing/tools/raster.py

@@ -52,80 +52,13 @@ def scanraster(layer, progress):
 
 
 def mapToPixel(mX, mY, geoTransform):
-    """Convert map coordinates to pixel coordinates.
-
-    @param mX              Input map X coordinate (double)
-    @param mY              Input map Y coordinate (double)
-    @param geoTransform    Input geotransform (six doubles)
-    @return pX, pY         Output coordinates (two doubles)
-    """
-
-    if geoTransform[2] + geoTransform[4] == 0:
-        pX = (mX - geoTransform[0]) / geoTransform[1]
-        pY = (mY - geoTransform[3]) / geoTransform[5]
-    else:
-        (pX, pY) = applyGeoTransform(mX, mY, invertGeoTransform(geoTransform))
+    (pX, pY) = gdal.ApplyGeoTransform(
+        gdal.InvGeoTransform(geoTransform)[1], mX, mY)
     return (int(pX), int(pY))
 
 
 def pixelToMap(pX, pY, geoTransform):
-    """Convert pixel coordinates to map coordinates.
-
-    @param pX              Input pixel X coordinate (double)
-    @param pY              Input pixel Y coordinate (double)
-    @param geoTransform    Input geotransform (six doubles)
-    @return mX, mY         Output coordinates (two doubles)
-    """
-
-    (mX, mY) = applyGeoTransform(pX + 0.5, pY + 0.5, geoTransform)
-    return (mX, mY)
-
-
-def applyGeoTransform(inX, inY, geoTransform):
-    """Apply a geotransform to coordinates.
-
-    @param inX             Input coordinate (double)
-    @param inY             Input coordinate (double)
-    @param geoTransform    Input geotransform (six doubles)
-    @return outX, outY     Output coordinates (two doubles)
-    """
-
-    outX = geoTransform[0] + inX * geoTransform[1] + inY * geoTransform[2]
-    outY = geoTransform[3] + inX * geoTransform[4] + inY * geoTransform[5]
-    return (outX, outY)
-
-
-def invertGeoTransform(geoTransform):
-    """Invert standard 3x2 set of geotransform coefficients.
-
-    @param geoTransform        Input GeoTransform (six doubles - unaltered)
-    @return outGeoTransform    Output GeoTransform (six doubles - updated)
-                               on success, None if the equation is uninvertable
-    """
-
-    # We assume a 3rd row that is [1 0 0]
-    # Compute determinate
-    det = geoTransform[1] * geoTransform[5] - geoTransform[2] * geoTransform[4]
-
-    if abs(det) < 0.000000000000001:
-        return
-
-    invDet = 1.0 / det
-
-    # Compute adjoint and divide by determinate
-    outGeoTransform = [0, 0, 0, 0, 0, 0]
-    outGeoTransform[1] = geoTransform[5] * invDet
-    outGeoTransform[4] = -geoTransform[4] * invDet
-
-    outGeoTransform[2] = -geoTransform[2] * invDet
-    outGeoTransform[5] = geoTransform[1] * invDet
-
-    outGeoTransform[0] = (geoTransform[2] * geoTransform[3] - geoTransform[0]
-                          * geoTransform[5]) * invDet
-    outGeoTransform[3] = (-geoTransform[1] * geoTransform[3] + geoTransform[0]
-                          * geoTransform[4]) * invDet
-
-    return outGeoTransform
+    return gdal.ApplyGeoTransform(geoTransform, pX + 0.5, pY + 0.5)
 
 
 class RasterWriter: