Looks like something automatically added tabs back in after I already fixed the white space. :/

samples/cpp/tutorial_code/gpu/gpu-thrust-interop/Thrust_interop.hpp

@@ -7,46 +7,46 @@
 #include <thrust/device_ptr.h>
 
 /*
-	@Brief step_functor is an object to correctly step a thrust iterator according to the stride of a matrix
+    @Brief step_functor is an object to correctly step a thrust iterator according to the stride of a matrix
 */
 //! [step_functor]
 template<typename T> struct step_functor : public thrust::unary_function<int, int>
 {
-	int columns;
-	int step;
-	int channels;
-	__host__ __device__ step_functor(int columns_, int step_, int channels_ = 1) : columns(columns_), step(step_), channels(channels_)	{	};
-	__host__ step_functor(cv::cuda::GpuMat& mat)
-	{
-		CV_Assert(mat.depth() == cv::DataType<T>::depth);
-		columns = mat.cols;
-		step = mat.step / sizeof(T);
-		channels = mat.channels();
-	}
-	__host__ __device__
-		int operator()(int x) const
-	{
-		int row = x / columns;
-		int idx = (row * step) + (x % columns)*channels;
-		return idx;
-	}
+    int columns;
+    int step;
+    int channels;
+    __host__ __device__ step_functor(int columns_, int step_, int channels_ = 1) : columns(columns_), step(step_), channels(channels_)	{	};
+    __host__ step_functor(cv::cuda::GpuMat& mat)
+    {
+        CV_Assert(mat.depth() == cv::DataType<T>::depth);
+        columns = mat.cols;
+        step = mat.step / sizeof(T);
+        channels = mat.channels();
+    }
+    __host__ __device__
+        int operator()(int x) const
+    {
+        int row = x / columns;
+        int idx = (row * step) + (x % columns)*channels; 
+        return idx;
+    }
 };
 //! [step_functor]
 //! [begin_itr]
 /*
-	@Brief GpuMatBeginItr returns a thrust compatible iterator to the beginning of a GPU mat's memory.
-	@Param mat is the input matrix
-	@Param channel is the channel of the matrix that the iterator is accessing.  If set to -1, the iterator will access every element in sequential order
+    @Brief GpuMatBeginItr returns a thrust compatible iterator to the beginning of a GPU mat's memory.
+    @Param mat is the input matrix
+    @Param channel is the channel of the matrix that the iterator is accessing.  If set to -1, the iterator will access every element in sequential order
 */
 template<typename T>
 thrust::permutation_iterator<thrust::device_ptr<T>, thrust::transform_iterator<step_functor<T>, thrust::counting_iterator<int>>>  GpuMatBeginItr(cv::cuda::GpuMat mat, int channel = 0)
 {
-	if (channel == -1)
-		mat = mat.reshape(1);
-	CV_Assert(mat.depth() == cv::DataType<T>::depth);
-	CV_Assert(channel < mat.channels());
-	return thrust::make_permutation_iterator(thrust::device_pointer_cast(mat.ptr<T>(0) + channel),
-		thrust::make_transform_iterator(thrust::make_counting_iterator(0), step_functor<T>(mat.cols, mat.step / sizeof(T), mat.channels())));
+    if (channel == -1)
+        mat = mat.reshape(1);
+    CV_Assert(mat.depth() == cv::DataType<T>::depth);
+    CV_Assert(channel < mat.channels());
+    return thrust::make_permutation_iterator(thrust::device_pointer_cast(mat.ptr<T>(0) + channel),
+        thrust::make_transform_iterator(thrust::make_counting_iterator(0), step_functor<T>(mat.cols, mat.step / sizeof(T), mat.channels())));
 }
 //! [begin_itr]
 //! [end_itr]
@@ -58,11 +58,11 @@ thrust::permutation_iterator<thrust::device_ptr<T>, thrust::transform_iterator<s
 template<typename T>
 thrust::permutation_iterator<thrust::device_ptr<T>, thrust::transform_iterator<step_functor<T>, thrust::counting_iterator<int>>>  GpuMatEndItr(cv::cuda::GpuMat mat, int channel = 0)
 {
-	if (channel == -1)
-		mat = mat.reshape(1);
-	CV_Assert(mat.depth() == cv::DataType<T>::depth);
-	CV_Assert(channel < mat.channels());
-	return thrust::make_permutation_iterator(thrust::device_pointer_cast(mat.ptr<T>(0) + channel),
-		thrust::make_transform_iterator(thrust::make_counting_iterator(mat.rows*mat.cols), step_functor<T>(mat.cols, mat.step / sizeof(T), mat.channels())));
+    if (channel == -1)
+        mat = mat.reshape(1);
+    CV_Assert(mat.depth() == cv::DataType<T>::depth);
+    CV_Assert(channel < mat.channels());
+    return thrust::make_permutation_iterator(thrust::device_pointer_cast(mat.ptr<T>(0) + channel),
+        thrust::make_transform_iterator(thrust::make_counting_iterator(mat.rows*mat.cols), step_functor<T>(mat.cols, mat.step / sizeof(T), mat.channels())));
 }
 //! [end_itr]