--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancStone/Sources/Scene2D/Internals/CairoFloatTextureRenderer.cpp	Tue Jul 07 16:21:02 2020 +0200
@@ -0,0 +1,109 @@
+/**
+ * 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 "CairoFloatTextureRenderer.h"
+
+#include "CairoColorTextureRenderer.h"
+#include "../FloatTextureSceneLayer.h"
+
+namespace OrthancStone
+{
+  namespace Internals
+  {
+    void CairoFloatTextureRenderer::Update(const ISceneLayer& layer)
+    {
+      const FloatTextureSceneLayer& l = dynamic_cast<const FloatTextureSceneLayer&>(layer);
+
+      textureTransform_ = l.GetTransform();
+      isLinearInterpolation_ = l.IsLinearInterpolation();
+
+      float windowCenter, windowWidth;
+      l.GetWindowing(windowCenter, windowWidth);
+
+      const float a = windowCenter - windowWidth / 2.0f;
+      const float slope = 256.0f / windowWidth;
+
+      const Orthanc::ImageAccessor& source = l.GetTexture();
+      const unsigned int width = source.GetWidth();
+      const unsigned int height = source.GetHeight();
+      texture_.SetSize(width, height, false);
+
+      Orthanc::ImageAccessor target;
+      texture_.GetWriteableAccessor(target);
+
+      assert(source.GetFormat() == Orthanc::PixelFormat_Float32 &&
+             target.GetFormat() == Orthanc::PixelFormat_BGRA32 &&
+             sizeof(float) == 4);
+
+      static const float LOG_NORMALIZATION = 255.0f / log(1.0f + 255.0f);
+      
+      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 - a) * slope;
+          if (v <= 0)
+          {
+            v = 0;
+          }
+          else if (v >= 255)
+          {
+            v = 255;
+          }
+
+          if (l.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);
+
+          if (l.IsInverted())
+          {
+            vv = 255 - vv;
+          }
+
+          q[0] = vv;
+          q[1] = vv;
+          q[2] = vv;
+
+          p++;
+          q += 4;
+        }
+      }
+    }
+
+      
+    void CairoFloatTextureRenderer::Render(const AffineTransform2D& transform,
+                                           unsigned int canvasWidth,
+                                           unsigned int canvasHeight)
+    {
+      CairoColorTextureRenderer::RenderColorTexture(target_, transform, texture_,
+                                                    textureTransform_, isLinearInterpolation_);
+    }
+  }
+}