Add colormap file support

application/CMakeLists.txt

@@ -10,6 +10,7 @@ configure_file("${CMAKE_CURRENT_SOURCE_DIR}/F3DConfig.h.in"
     "${CMAKE_CURRENT_BINARY_DIR}/F3DConfig.h")
 
 set(F3D_SOURCE_FILES
+  ${CMAKE_CURRENT_SOURCE_DIR}/F3DColorMapTools.cxx
   ${CMAKE_CURRENT_SOURCE_DIR}/F3DConfigFileTools.cxx
   ${CMAKE_CURRENT_BINARY_DIR}/F3DIcon.cxx
   ${CMAKE_CURRENT_SOURCE_DIR}/F3DOptionsParser.cxx
@@ -182,6 +183,13 @@ install(
   COMPONENT configuration
   EXCLUDE_FROM_ALL)
 
+# Default color maps
+install(
+  DIRECTORY "${F3D_SOURCE_DIR}/resources/colormaps/"
+  DESTINATION "${f3d_config_dir}"
+  COMPONENT colormaps
+  EXCLUDE_FROM_ALL)
+
 # Other ressoure files
 if(UNIX AND NOT APPLE AND NOT ANDROID)
   install(FILES "${F3D_SOURCE_DIR}/resources/f3d.desktop"

application/F3DColorMapTools.cxx

@@ -0,0 +1,61 @@
+#include "F3DColorMapTools.h"
+
+#include "image.h"
+
+#include <filesystem>
+
+// todo: remove
+#include <iostream>
+
+namespace fs = std::filesystem;
+
+namespace F3DColorMapTools
+{
+std::string Find(const std::string& str)
+{
+  if (fs::exists(str))
+  {
+    // already full path;
+    return str;
+  }
+
+  // todo: stem, find file in standard paths
+
+  return {};
+}
+
+std::vector<double> Read(const std::string& path)
+{
+  try
+  {
+    f3d::image img(path);
+
+    if (img.getChannelCount() < 3)
+    {
+      // TODO: warning
+      return {};
+    }
+
+    int w = img.getWidth();
+
+    std::vector<double> cm;
+    cm.resize(4 * w);
+
+    for (int i = 0; i < w; i++)
+    {
+      cm[4 * i] = static_cast<double>(i) / w;
+      for (int j = 0; j < 3; j++)
+      {
+        cm[4 * i + j + 1] = img(i, 0, j);
+      }
+    }
+
+    return cm;
+  }
+  catch (const f3d::image::read_exception&)
+  {
+    // TODO
+    return {};
+  }
+}
+}

application/F3DColorMapTools.h

@@ -0,0 +1,19 @@
+/**
+ * @class   F3DColorMapReader
+ * @brief   A class used to convert images to libf3d colormap option
+ *
+ */
+
+#ifndef F3DColorMapReader_h
+#define F3DColorMapReader_h
+
+#include <string>
+#include <vector>
+
+namespace F3DColorMapTools
+{
+std::string Find(const std::string& str);
+std::vector<double> Read(const std::string& path);
+}
+
+#endif

application/F3DConfigFileTools.h

@@ -14,7 +14,6 @@ namespace F3DConfigFileTools
 {
 std::filesystem::path GetUserConfigFileDirectory();
 std::filesystem::path GetBinaryConfigFileDirectory();
-std::filesystem::path GetSystemConfigFileDirectory();
 std::filesystem::path GetConfigPath(const std::string& configSearch);
 }
 

application/F3DOptionsParser.cxx

@@ -379,6 +379,7 @@ void ConfigurationOptions::GetOptions(F3DAppOptions& appOptions, f3d::options& o
     this->DeclareOption(grp4, "cells", "c", "Use a scalar array from the cells", options.getAsBoolRef("model.scivis.cells"), HasDefault::YES, MayHaveConfig::YES);
     this->DeclareOption(grp4, "range", "", "Custom range for the coloring by array", options.getAsDoubleVectorRef("model.scivis.range"), HasDefault::YES, MayHaveConfig::YES, "<min,max>");
     this->DeclareOption(grp4, "bar", "b", "Show scalar bar", options.getAsBoolRef("ui.bar"), HasDefault::YES, MayHaveConfig::YES);
+    this->DeclareOption(grp4, "colormap-file", "", "Specify a colormap image (ignored if \"colormap\" is specified)", appOptions.UserColorMap, HasDefault::YES, MayHaveConfig::YES, "<TODO>");
     this->DeclareOption(grp4, "colormap", "", "Specify a custom colormap", options.getAsDoubleVectorRef("model.scivis.colormap"), HasDefault::YES, MayHaveConfig::YES, "<color_list>");
     this->DeclareOption(grp4, "volume", "v", "Show volume if the file is compatible", options.getAsBoolRef("model.volume.enable"), HasDefault::YES, MayHaveConfig::YES);
     this->DeclareOption(grp4, "inverse", "i", "Inverse opacity function for volume rendering", options.getAsBoolRef("model.volume.inverse"), HasDefault::YES, MayHaveConfig::YES);

application/F3DOptionsParser.h

@@ -20,6 +20,7 @@ class options;
 struct F3DAppOptions
 {
   std::string UserConfigFile = "";
+  std::string UserColorMap = "";
   bool DryRun = false;
   bool GeometryOnly = false;
   bool GroupGeometries = false;

application/F3DStarter.cxx

@@ -1,5 +1,6 @@
 #include "F3DStarter.h"
 
+#include "F3DColorMapTools.h"
 #include "F3DConfig.h"
 #include "F3DIcon.h"
 #include "F3DNSDelegate.h"
@@ -313,6 +314,31 @@ int F3DStarter::Start(int argc, char** argv)
     }
 #endif
   }
+
+  // Parse colormap
+  if (!this->Internals->AppOptions.UserColorMap.empty())
+  {
+    std::string fullPath = F3DColorMapTools::Find(this->Internals->AppOptions.UserColorMap);
+
+    if (!fullPath.empty())
+    {
+      auto cm = F3DColorMapTools::Read(fullPath);
+
+      if (!cm.empty())
+      {
+        this->Internals->Engine->getOptions().set("model.scivis.colormap", cm);
+      }
+      else
+      {
+        // TODO: warning
+      }
+    }
+    else
+    {
+      // TODO: warning
+    }
+  }
+
   f3d::log::debug("Engine configured");
 
   f3d::log::debug("========== Loading 3D file ==========");

application/testing/CMakeLists.txt

@@ -197,6 +197,7 @@ f3d_test(NAME TestUpDirectionNoSign DATA suzanne.ply ARGS --up=X DEFAULT_LIGHTS)
 f3d_test(NAME TestTextureMatCap DATA suzanne.ply ARGS --texture-matcap=${F3D_SOURCE_DIR}/testing/data/skin.png DEFAULT_LIGHTS)
 f3d_test(NAME TestTextureMatCapWithTCoords DATA WaterBottle.glb ARGS --geometry-only --texture-matcap=${F3D_SOURCE_DIR}/testing/data/skin.png DEFAULT_LIGHTS)
 f3d_test(NAME TestConfigOrder DATA suzanne.ply ARGS CONFIG ${F3D_SOURCE_DIR}/testing/data/config-order.json DEFAULT_LIGHTS)
+f3d_test(NAME TestColorMapFileFullPath DATA dragon.vtu ARGS --colormap-file=${F3D_SOURCE_DIR}/resources/colormaps/viridis.png --scalars --comp=1 DEFAULT_LIGHTS)
 
 # Needs SSBO: https://gitlab.kitware.com/vtk/vtk/-/merge_requests/10675
 if(VTK_VERSION VERSION_GREATER_EQUAL 9.3.20231108)

doc/user/OPTIONS.md

@@ -83,6 +83,7 @@ Options|Default|Description
 -c, \-\-cells||Specify that the scalar array is to be found *on the cells* instead of on the points.<br>Use with the scalar option.
 \-\-range=\<min,max\>||Set a *custom range for the coloring* by the array.<br>Use with the scalar option.
 -b, \-\-bar||Show *scalar bar* of the coloring by array.<br>Use with the scalar option.
+\-\-colormap\-file=\<name\>||Set a *colormap file for the coloring*.<br>Valid values are inferno, todo, todo.<br>Use with the scalar option.
 \-\-colormap=\<color_list\>||Set a *custom colormap for the coloring*.<br>This is a list of colors in the format `val1,red1,green1,blue1,...,valN,redN,greenN,blueN`<br>where all values are in the range (0,1).<br>Use with the scalar option.
 -v, \-\-volume||Enable *volume rendering*. It is only available for 3D image data (vti, dcm, nrrd, mhd files) and will display nothing with other formats.
 -i, \-\-inverse||Inverse the linear opacity function used for volume rendering.

library/public/image.h

@@ -85,6 +85,11 @@ class F3D_EXPORT image
   bool operator!=(const image& reference) const;
   ///@}
 
+  /**
+   * TODO: doc
+   */
+  double operator()(int x, int y, int channel) const;
+
   /**
    * Get the list of supported image format when opening a file.
    */

library/src/image.cxx

@@ -353,6 +353,24 @@ bool image::operator!=(const image& reference) const
   return !this->operator==(reference);
 }
 
+//----------------------------------------------------------------------------
+double image::operator()(int x, int y, int channel) const
+{
+  double v = this->Internals->Image->GetScalarComponentAsDouble(x, y, 0, channel);
+
+  switch (getChannelType())
+  {
+    case ChannelType::BYTE:
+      return v / 255.0;
+    case ChannelType::SHORT:
+      return v / 65535.0;
+    default:
+      break;
+  }
+
+  return v;
+}
+
 //----------------------------------------------------------------------------
 void image::save(const std::string& path, SaveFormat format) const
 {