Fix T45617: Map UV node produces image artifacts

Basically filtering was happening twice, first time by applying weights of EWA
filter itself and then by applying subpixel offset while reading pixel values.

8 files changed, 15 insertions, 48 deletions

diff --git a/source/blender/compositor/intern/COM_MemoryBuffer.cpp b/source/blender/compositor/intern/COM_MemoryBuffer.cpp
index 2dbf0a6aa46..162e08a95a6 100644
--- a/source/blender/compositor/intern/COM_MemoryBuffer.cpp
+++ b/source/blender/compositor/intern/COM_MemoryBuffer.cpp
@@ -195,45 +195,15 @@ void MemoryBuffer::addPixel(int x, int y, const float color[4])
 	}
 }
 
-typedef struct ReadEWAData {
-	MemoryBuffer *buffer;
-	PixelSampler sampler;
-	float ufac, vfac;
-} ReadEWAData;
-
 static void read_ewa_pixel_sampled(void *userdata, int x, int y, float result[4])
 {
-	ReadEWAData *data = (ReadEWAData *) userdata;
-	switch (data->sampler) {
-		case COM_PS_NEAREST:
-			data->buffer->read(result, x, y);
-			break;
-		case COM_PS_BILINEAR:
-			data->buffer->readBilinear(result,
-			                           (float)x + data->ufac,
-			                           (float)y + data->vfac);
-			break;
-		case COM_PS_BICUBIC:
-			/* TOOD(sergey): no readBicubic method yet */
-			data->buffer->readBilinear(result,
-			                           (float)x + data->ufac,
-			                           (float)y + data->vfac);
-			break;
-		default:
-			zero_v4(result);
-			break;
-	}
+	MemoryBuffer *buffer = (MemoryBuffer *) userdata;
+	buffer->read(result, x, y);
 }
 
-void MemoryBuffer::readEWA(float *result, const float uv[2], const float derivatives[2][2], PixelSampler sampler)
+void MemoryBuffer::readEWA(float *result, const float uv[2], const float derivatives[2][2])
 {
 	BLI_assert(this->m_datatype == COM_DT_COLOR);
-	ReadEWAData data;
-	data.buffer = this;
-	data.sampler = sampler;
-	data.ufac = uv[0] - floorf(uv[0]);
-	data.vfac = uv[1] - floorf(uv[1]);
-
 	int width = this->getWidth(), height = this->getHeight();
 	/* TODO(sergey): Render pipeline uses normalized coordinates and derivatives,
 	 * but compositor uses pixel space. For now let's just divide the values and
@@ -248,6 +218,6 @@ void MemoryBuffer::readEWA(float *result, const float uv[2], const float derivat
 	               true,
 	               uv_normal, du_normal, dv_normal,
 	               read_ewa_pixel_sampled,
-	               &data,
+	               this,
 	               result);
 }
diff --git a/source/blender/compositor/intern/COM_MemoryBuffer.h b/source/blender/compositor/intern/COM_MemoryBuffer.h
index 0b5fc21e69e..de8c14e1a66 100644
--- a/source/blender/compositor/intern/COM_MemoryBuffer.h
+++ b/source/blender/compositor/intern/COM_MemoryBuffer.h
@@ -262,7 +262,7 @@ public:
 		BLI_bilinear_interpolation_fl(this->m_buffer, result, this->m_width, this->m_height, this->m_num_channels, u, v);
 	}
 
-	void readEWA(float *result, const float uv[2], const float derivatives[2][2], PixelSampler sampler);
+	void readEWA(float *result, const float uv[2], const float derivatives[2][2]);
 	
 	/**
 	 * @brief is this MemoryBuffer a temporarily buffer (based on an area, not on a chunk)
diff --git a/source/blender/compositor/intern/COM_SocketReader.h b/source/blender/compositor/intern/COM_SocketReader.h
index 7ba208ebbf6..ab8a3c06ef5 100644
--- a/source/blender/compositor/intern/COM_SocketReader.h
+++ b/source/blender/compositor/intern/COM_SocketReader.h
@@ -93,8 +93,7 @@ protected:
 	 */
 	virtual void executePixelFiltered(float /*output*/[4],
 	                                  float /*x*/, float /*y*/,
-	                                  float /*dx*/[2], float /*dy*/[2],
-	                                  PixelSampler /*sampler*/) {}
+	                                  float /*dx*/[2], float /*dy*/[2]) {}
 
 public:
 	inline void readSampled(float result[4], float x, float y, PixelSampler sampler) {
@@ -103,8 +102,8 @@ public:
 	inline void read(float result[4], int x, int y, void *chunkData) {
 		executePixel(result, x, y, chunkData);
 	}
-	inline void readFiltered(float result[4], float x, float y, float dx[2], float dy[2], PixelSampler sampler) {
-		executePixelFiltered(result, x, y, dx, dy, sampler);
+	inline void readFiltered(float result[4], float x, float y, float dx[2], float dy[2]) {
+		executePixelFiltered(result, x, y, dx, dy);
 	}
 
 	virtual void *initializeTileData(rcti * /*rect*/) { return 0; }
diff --git a/source/blender/compositor/operations/COM_DisplaceOperation.cpp b/source/blender/compositor/operations/COM_DisplaceOperation.cpp
index 6dfef8a0a11..9b3377e887a 100644
--- a/source/blender/compositor/operations/COM_DisplaceOperation.cpp
+++ b/source/blender/compositor/operations/COM_DisplaceOperation.cpp
@@ -60,7 +60,7 @@ void DisplaceOperation::executePixelSampled(float output[4], float x, float y, P
 	}
 	else {
 		/* EWA filtering (without nearest it gets blurry with NO distortion) */
-		this->m_inputColorProgram->readFiltered(output, uv[0], uv[1], deriv[0], deriv[1], COM_PS_BILINEAR);
+		this->m_inputColorProgram->readFiltered(output, uv[0], uv[1], deriv[0], deriv[1]);
 	}
 }
 
diff --git a/source/blender/compositor/operations/COM_MapUVOperation.cpp b/source/blender/compositor/operations/COM_MapUVOperation.cpp
index ffa48ce3956..d091675286d 100644
--- a/source/blender/compositor/operations/COM_MapUVOperation.cpp
+++ b/source/blender/compositor/operations/COM_MapUVOperation.cpp
@@ -53,7 +53,7 @@ void MapUVOperation::executePixelSampled(float output[4], float x, float y, Pixe
 	}
 
 	/* EWA filtering */
-	this->m_inputColorProgram->readFiltered(output, uv[0], uv[1], deriv[0], deriv[1], COM_PS_BILINEAR);
+	this->m_inputColorProgram->readFiltered(output, uv[0], uv[1], deriv[0], deriv[1]);
 	
 	/* UV to alpha threshold */
 	const float threshold = this->m_alpha * 0.05f;
diff --git a/source/blender/compositor/operations/COM_PlaneDistortCommonOperation.cpp b/source/blender/compositor/operations/COM_PlaneDistortCommonOperation.cpp
index d7d1c9c0c93..1145abd076a 100644
--- a/source/blender/compositor/operations/COM_PlaneDistortCommonOperation.cpp
+++ b/source/blender/compositor/operations/COM_PlaneDistortCommonOperation.cpp
@@ -108,8 +108,7 @@ void PlaneDistortWarpImageOperation::executePixelSampled(float output[4], float
 		warpCoord(x, y, this->m_samples[0].perspectiveMatrix, uv, deriv);
 		m_pixelReader->readFiltered(output,
 		                            uv[0], uv[1],
-		                            deriv[0], deriv[1],
-		                            COM_PS_BILINEAR);
+		                            deriv[0], deriv[1]);
 	}
 	else {
 		zero_v4(output);
@@ -118,8 +117,7 @@ void PlaneDistortWarpImageOperation::executePixelSampled(float output[4], float
 			warpCoord(x, y, this->m_samples[sample].perspectiveMatrix, uv, deriv);
 			m_pixelReader->readFiltered(color,
 			                            uv[0], uv[1],
-			                            deriv[0], deriv[1],
-			                            COM_PS_BILINEAR);
+			                            deriv[0], deriv[1]);
 			add_v4_v4(output, color);
 		}
 		mul_v4_fl(output, 1.0f / (float)this->m_motion_blur_samples);
diff --git a/source/blender/compositor/operations/COM_ReadBufferOperation.cpp b/source/blender/compositor/operations/COM_ReadBufferOperation.cpp
index bf0f24e06be..6dbe132257a 100644
--- a/source/blender/compositor/operations/COM_ReadBufferOperation.cpp
+++ b/source/blender/compositor/operations/COM_ReadBufferOperation.cpp
@@ -89,7 +89,7 @@ void ReadBufferOperation::executePixelExtend(float output[4], float x, float y,
 	}
 }
 
-void ReadBufferOperation::executePixelFiltered(float output[4], float x, float y, float dx[2], float dy[2], PixelSampler sampler)
+void ReadBufferOperation::executePixelFiltered(float output[4], float x, float y, float dx[2], float dy[2])
 {
 	if (m_single_value) {
 		/* write buffer has a single value stored at (0,0) */
@@ -98,7 +98,7 @@ void ReadBufferOperation::executePixelFiltered(float output[4], float x, float y
 	else {
 		const float uv[2] = { x, y };
 		const float deriv[2][2] = { {dx[0], dx[1]}, {dy[0], dy[1]} };
-		m_buffer->readEWA(output, uv, deriv, sampler);
+		m_buffer->readEWA(output, uv, deriv);
 	}
 }
 
diff --git a/source/blender/compositor/operations/COM_ReadBufferOperation.h b/source/blender/compositor/operations/COM_ReadBufferOperation.h
index 7e5bc55a8ca..cd706ed0b75 100644
--- a/source/blender/compositor/operations/COM_ReadBufferOperation.h
+++ b/source/blender/compositor/operations/COM_ReadBufferOperation.h
@@ -43,7 +43,7 @@ public:
 	void executePixelSampled(float output[4], float x, float y, PixelSampler sampler);
 	void executePixelExtend(float output[4], float x, float y, PixelSampler sampler,
 	                        MemoryBufferExtend extend_x, MemoryBufferExtend extend_y);
-	void executePixelFiltered(float output[4], float x, float y, float dx[2], float dy[2], PixelSampler sampler);
+	void executePixelFiltered(float output[4], float x, float y, float dx[2], float dy[2]);
 	const bool isReadBufferOperation() const { return true; }
 	void setOffset(unsigned int offset) { this->m_offset = offset; }
 	unsigned int getOffset() const { return this->m_offset; }