added Bitmap::copyFrom method

include/mitsuba/core/bitmap.h

@@ -771,9 +771,58 @@ public:
 	 */
 	void applyMatrix(Float matrix[3][3]);
 
+	/**
+	 * \brief Copy the contents of another bitmap into the
+	 * region with the specified offset
+	 *
+	 * Out-of-bounds regions are ignored. It is assumed that
+	 * <tt>bitmap != this</tt>.
+	 *
+	 * \remark This function throws an exception when the bitmaps
+	 * use different component formats or channels, or when the
+	 * component format is \ref EBitmask.
+	 */
+	void copyFrom(const Bitmap *bitmap, Point2i sourceOffset,
+			Point2i targetOffset, Vector2i size);
+
+	/**
+	 * \brief Copy the contents of another bitmap into the
+	 * region with the specified offset
+	 *
+	 * This convenience function calls the main <tt>copyFrom()</tt>
+	 * implementation with <tt>size</tt> set to <tt>bitmap->getSize()</tt>
+	 * and <tt>sourceOffset</tt> set to zero. Out-of-bounds regions are
+	 * ignored. It is assumed that <tt>bitmap != this</tt>.
+	 *
+	 * \remark This function throws an exception when the bitmaps
+	 * use different component formats or channels, or when the
+	 * component format is \ref EBitmask.
+	 */
+	inline void copyFrom(const Bitmap *bitmap, Point2i targetOffset) {
+		copyFrom(bitmap, Point2i(0), targetOffset, bitmap->getSize());
+	}
+
+	/**
+	 * \brief Copy the contents of another bitmap into the
+	 * region with the specified offset
+	 *
+	 * This convenience function calls the main <tt>copyFrom()</tt>
+	 * implementation with <tt>size</tt> set to <tt>bitmap->getSize()</tt>
+	 * and <tt>sourceOffset</tt> and <tt>targetOffset</tt>tt> set to zero.
+	 * Out-of-bounds regions are ignored. It is assumed
+	 * that <tt>bitmap != this</tt>.
+	 *
+	 * \remark This function throws an exception when the bitmaps
+	 * use different component formats or channels, or when the
+	 * component format is \ref EBitmask.
+	 */
+	inline void copyFrom(const Bitmap *bitmap) {
+		copyFrom(bitmap, Point2i(0), Point2i(0), bitmap->getSize());
+	}
+
 	/**
 	 * \brief Accumulate the contents of another bitmap into the
-	 * region of the specified offset
+	 * region with the specified offset
 	 *
 	 * Out-of-bounds regions are ignored. It is assumed that
 	 * <tt>bitmap != this</tt>.
@@ -784,9 +833,10 @@ public:
 	 */
 	void accumulate(const Bitmap *bitmap, Point2i sourceOffset,
 			Point2i targetOffset, Vector2i size);
+
 	/**
 	 * \brief Accumulate the contents of another bitmap into the
-	 * region of the specified offset
+	 * region with the specified offset
 	 *
 	 * This convenience function calls the main <tt>accumulate()</tt>
 	 * implementation with <tt>size</tt> set to <tt>bitmap->getSize()</tt>
@@ -803,7 +853,7 @@ public:
 
 	/**
 	 * \brief Accumulate the contents of another bitmap into the
-	 * region of the specified offset
+	 * region with the specified offset
 	 *
 	 * This convenience function calls the main <tt>accumulate()</tt>
 	 * implementation with <tt>size</tt> set to <tt>bitmap->getSize()</tt>

src/libcore/bitmap.cpp

@@ -514,6 +514,52 @@ ref<Bitmap> Bitmap::rotateFlip(ERotateFlipType type) const {
 	return result;
 }
 
+void Bitmap::copyFrom(const Bitmap *bitmap, Point2i sourceOffset,
+		Point2i targetOffset, Vector2i size) {
+
+	if (m_componentFormat == EBitmask)
+		Log(EError, "Bitmap::copy(): bitmasks are not supported!");
+
+	Assert(getPixelFormat() == bitmap->getPixelFormat() &&
+	       getComponentFormat() == bitmap->getComponentFormat() &&
+	       getChannelCount() == bitmap->getChannelCount());
+
+	Vector2i offsetIncrease(
+		std::max(0, std::max(-sourceOffset.x, -targetOffset.x)),
+		std::max(0, std::max(-sourceOffset.y, -targetOffset.y))
+	);
+
+	sourceOffset += offsetIncrease;
+	targetOffset += offsetIncrease;
+	size -= offsetIncrease;
+
+	Vector2i sizeDecrease(
+		std::max(0, std::max(sourceOffset.x + size.x - bitmap->getWidth(), targetOffset.x + size.x - getWidth())),
+		std::max(0, std::max(sourceOffset.y + size.y - bitmap->getHeight(), targetOffset.y + size.y - getHeight())));
+
+	size -= sizeDecrease;
+
+	if (size.x <= 0 || size.y <= 0)
+		return;
+
+	const size_t
+		pixelStride  = getBytesPerPixel(),
+		sourceStride = bitmap->getWidth() * pixelStride,
+		targetStride = getWidth() * pixelStride;
+
+	const uint8_t *source = bitmap->getUInt8Data() +
+		(sourceOffset.x + sourceOffset.y * (size_t) bitmap->getWidth()) * pixelStride;
+
+	uint8_t *target = m_data +
+		(targetOffset.x + targetOffset.y * (size_t) m_size.x) * pixelStride;
+
+	for (int y = 0; y < size.y; ++y) {
+		memcpy(target, source, size.x * getBytesPerPixel());
+		source += sourceStride;
+		target += targetStride;
+	}
+}
+
 void Bitmap::accumulate(const Bitmap *bitmap, Point2i sourceOffset,
 		Point2i targetOffset, Vector2i size) {
 	Assert(getPixelFormat() == bitmap->getPixelFormat() &&

src/libpython/core.cpp

@@ -1235,6 +1235,9 @@ void export_core() {
 	void (Bitmap::*accumulate_1)(const Bitmap *bitmap, Point2i sourceOffset, Point2i targetOffset, Vector2i size) = &Bitmap::accumulate;
 	void (Bitmap::*accumulate_2)(const Bitmap *bitmap, Point2i targetOffset) = &Bitmap::accumulate;
 	void (Bitmap::*accumulate_3)(const Bitmap *bitmap) = &Bitmap::accumulate;
+	void (Bitmap::*copyFrom_1)(const Bitmap *bitmap, Point2i sourceOffset, Point2i targetOffset, Vector2i size) = &Bitmap::copyFrom;
+	void (Bitmap::*copyFrom_2)(const Bitmap *bitmap, Point2i targetOffset) = &Bitmap::copyFrom;
+	void (Bitmap::*copyFrom_3)(const Bitmap *bitmap) = &Bitmap::copyFrom;
 	const Properties &(Bitmap::*get_metadata)() const = &Bitmap::getMetadata;
 
 	void (Bitmap::*resample_1)(const ReconstructionFilter *,
@@ -1283,6 +1286,9 @@ void export_core() {
 		.def("accumulate", accumulate_1)
 		.def("accumulate", accumulate_2)
 		.def("accumulate", accumulate_3)
+		.def("copyFrom", copyFrom_1)
+		.def("copyFrom", copyFrom_2)
+		.def("copyFrom", copyFrom_3)
 		.def("convolve", &Bitmap::convolve)
 		.def("arithmeticOperation", &Bitmap::arithmeticOperation, BP_RETURN_VALUE)
 		.def("resample", resample_1)