--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancStone/Sources/Scene2D/LookupTableTextureSceneLayer.cpp	Tue Jul 07 16:21:02 2020 +0200
@@ -0,0 +1,311 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "LookupTableTextureSceneLayer.h"
+
+#include <Images/Image.h>
+#include <Images/ImageProcessing.h>
+#include <OrthancException.h>
+
+namespace OrthancStone
+{
+  LookupTableTextureSceneLayer::LookupTableTextureSceneLayer(const Orthanc::ImageAccessor& texture) :
+    applyLog_(false)
+  {
+    {
+      std::unique_ptr<Orthanc::ImageAccessor> t(
+        new Orthanc::Image(Orthanc::PixelFormat_Float32, 
+                           texture.GetWidth(), 
+                           texture.GetHeight(), 
+                           false));
+
+      Orthanc::ImageProcessing::Convert(*t, texture);
+      SetTexture(t.release());
+    }
+
+    SetLookupTableGrayscale(); // simple ramp between 0 and 255
+    SetRange(0, 1);
+  }
+
+
+  void LookupTableTextureSceneLayer::SetLookupTableGrayscale()
+  {
+    std::vector<uint8_t> rgb(3 * 256);
+
+    for (size_t i = 0; i < 256; i++)
+    {
+      rgb[3 * i]     = static_cast<uint8_t>(i);
+      rgb[3 * i + 1] = static_cast<uint8_t>(i);
+      rgb[3 * i + 2] = static_cast<uint8_t>(i);
+    }
+
+    SetLookupTableRgb(rgb);
+  }  
+
+
+  void LookupTableTextureSceneLayer::SetLookupTableRgb(const std::vector<uint8_t>& lut)
+  {
+    if (lut.size() != 3 * 256)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError);
+    }
+
+    lut_.resize(4 * 256);
+
+    for (size_t i = 0; i < 256; i++)
+    {
+      // Premultiplied alpha
+      
+      if (i == 0)
+      {
+        // Make zero transparent
+        lut_[4 * i] = 0;        // R
+        lut_[4 * i + 1] = 0;    // G
+        lut_[4 * i + 2] = 0;    // B
+        lut_[4 * i + 3] = 0;    // A
+      }
+      else
+      {
+        float a = static_cast<float>(i) / 255.0f;
+        
+        float r = static_cast<float>(lut[3 * i]) * a;
+        float g = static_cast<float>(lut[3 * i + 1]) * a;
+        float b = static_cast<float>(lut[3 * i + 2]) * a;
+        
+        lut_[4 * i] = static_cast<uint8_t>(std::floor(r));
+        lut_[4 * i + 1] = static_cast<uint8_t>(std::floor(g));
+        lut_[4 * i + 2] = static_cast<uint8_t>(std::floor(b));
+        lut_[4 * i + 3] = static_cast<uint8_t>(std::floor(a * 255.0f));
+      }
+    }
+
+    IncrementRevision();
+  }
+
+
+  void LookupTableTextureSceneLayer::SetLookupTable(const std::vector<uint8_t>& lut)
+  {
+    if (lut.size() == 4 * 256)
+    {
+      lut_ = lut;
+      IncrementRevision();
+    }
+    else if (lut.size() == 3 * 256)
+    {
+      SetLookupTableRgb(lut);
+    }
+    else
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+  }
+
+  void LookupTableTextureSceneLayer::SetRange(float minValue,
+                                              float maxValue)
+  {
+    if (minValue > maxValue)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+    else
+    {
+      minValue_ = minValue;
+      maxValue_ = maxValue;
+      IncrementRevision();
+    }
+  }
+
+  void LookupTableTextureSceneLayer::SetApplyLog(bool apply)
+  {
+    applyLog_ = apply;
+    IncrementRevision();
+  }
+
+  void LookupTableTextureSceneLayer::FitRange()
+  {
+    Orthanc::ImageProcessing::GetMinMaxFloatValue(minValue_, maxValue_, GetTexture());
+    assert(minValue_ <= maxValue_);
+    // TODO: debug to be removed
+    if (fabs(maxValue_ - minValue_) < 0.0001) {
+      LOG(INFO) << "LookupTableTextureSceneLayer::FitRange(): minValue_ = " << minValue_ << " maxValue_ = " << maxValue_;
+    }
+    IncrementRevision();
+  }
+
+    
+  ISceneLayer* LookupTableTextureSceneLayer::Clone() const
+  {
+    std::unique_ptr<LookupTableTextureSceneLayer> cloned
+      (new LookupTableTextureSceneLayer(GetTexture()));
+
+
+    // TODO: why is windowing_ not copied??????
+    cloned->CopyParameters(*this);
+    cloned->minValue_ = minValue_;
+    cloned->maxValue_ = maxValue_;
+    cloned->lut_ = lut_;
+
+    return cloned.release();
+  }
+
+
+  // Templatized function to speed up computations, by avoiding
+  // testing conditions on each pixel
+  template <bool IsApplyLog,
+            Orthanc::PixelFormat TargetFormat>
+  static void RenderInternal(Orthanc::ImageAccessor& target,
+                             const Orthanc::ImageAccessor& source,
+                             float minValue,
+                             float slope,
+                             const std::vector<uint8_t>& lut)
+  {
+    static const float LOG_NORMALIZATION = 255.0f / log(1.0f + 255.0f);
+
+    const unsigned int width = source.GetWidth();
+    const unsigned int height = source.GetHeight();
+    
+    for (unsigned int y = 0; y < height; y++)
+    {
+      const float* p = reinterpret_cast<const float*>(source.GetConstRow(y));
+      uint8_t* q = reinterpret_cast<uint8_t*>(target.GetRow(y));
+
+      for (unsigned int x = 0; x < width; x++)
+      {
+        float v = (*p - minValue) * slope;
+        if (v <= 0)
+        {
+          v = 0;
+        }
+        else if (v >= 255)
+        {
+          v = 255;
+        }
+
+        if (IsApplyLog)
+        {
+          // https://theailearner.com/2019/01/01/log-transformation/
+          v = LOG_NORMALIZATION * log(1.0f + static_cast<float>(v));
+        }
+
+        assert(v >= 0.0f && v <= 255.0f);
+
+        uint8_t vv = static_cast<uint8_t>(v);
+
+        switch (TargetFormat)
+        {
+          case Orthanc::PixelFormat_BGRA32:
+            // For Cairo surfaces
+            q[0] = lut[4 * vv + 2];  // B
+            q[1] = lut[4 * vv + 1];  // G
+            q[2] = lut[4 * vv + 0];  // R
+            q[3] = lut[4 * vv + 3];  // A
+            break;
+
+          case Orthanc::PixelFormat_RGBA32:
+            // For OpenGL
+            q[0] = lut[4 * vv + 0];  // R
+            q[1] = lut[4 * vv + 1];  // G
+            q[2] = lut[4 * vv + 2];  // B
+            q[3] = lut[4 * vv + 3];  // A
+            break;
+
+          default:
+            assert(0);
+        }
+            
+        p++;
+        q += 4;
+      }
+    }
+  }
+  
+
+  void LookupTableTextureSceneLayer::Render(Orthanc::ImageAccessor& target) const
+  {
+    assert(sizeof(float) == 4);
+
+    if (!HasTexture())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
+    }
+
+    const Orthanc::ImageAccessor& source = GetTexture();
+    
+    if (source.GetFormat() != Orthanc::PixelFormat_Float32 ||
+        (target.GetFormat() != Orthanc::PixelFormat_RGBA32 &&
+         target.GetFormat() != Orthanc::PixelFormat_BGRA32))
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_IncompatibleImageFormat);
+    }
+
+    if (source.GetWidth() != target.GetWidth() ||
+        source.GetHeight() != target.GetHeight())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_IncompatibleImageSize);
+    }
+
+    const float minValue = GetMinValue();
+    float slope;
+
+    if (GetMinValue() >= GetMaxValue())
+    {
+      slope = 0;
+    }
+    else
+    {
+      slope = 256.0f / (GetMaxValue() - GetMinValue());
+    }
+
+    const std::vector<uint8_t>& lut = GetLookupTable();
+    if (lut.size() != 4 * 256)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError);
+    }
+
+    switch (target.GetFormat())
+    {
+      case Orthanc::PixelFormat_RGBA32:
+        if (applyLog_)
+        {
+          RenderInternal<true, Orthanc::PixelFormat_RGBA32>(target, source, minValue, slope, lut);
+        }
+        else
+        {
+          RenderInternal<false, Orthanc::PixelFormat_RGBA32>(target, source, minValue, slope, lut);
+        }
+        break;
+
+      case Orthanc::PixelFormat_BGRA32:
+        if (applyLog_)
+        {
+          RenderInternal<true, Orthanc::PixelFormat_BGRA32>(target, source, minValue, slope, lut);
+        }
+        else
+        {
+          RenderInternal<false, Orthanc::PixelFormat_BGRA32>(target, source, minValue, slope, lut);
+        }
+        break;
+
+      default:
+        throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError);
+    }
+  }
+}