diff --git a/CMakeLists.txt b/CMakeLists.txt
index 19f7b04..d3ca3c3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -80,6 +80,6 @@ set_target_properties(poncaplot PROPERTIES RUNTIME_OUTPUT_DIRECTORY $<1:${CMAKE_
 
 # Fix compilation error with MSVC
 if (MSVC)
-  target_compile_options(poncaplot PRIVATE /bigobj)
+  target_compile_options(poncaplot PRIVATE /bigobj -openmp:llvm)
 endif ()
 
diff --git a/README.md b/README.md
index bb66883..81136fd 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,9 @@
 # poncaplot
-2d plot application displaying scalar/vector fields reconstructed using Ponca
-![image](https://github.com/poncateam/poncaplot/assets/6310221/75ad8c69-98af-43b7-9148-7123319b2760)
-![image](https://github.com/poncateam/poncaplot/assets/6310221/b1b388b3-ad28-47d1-9f20-a44ab19ad796)
+2d plot application displaying scalar fields reconstructed using [Ponca](https://poncateam.github.io/ponca/)
+
+
+
+
+https://github.com/poncateam/poncaplot/assets/6310221/a1885def-4135-4afa-b833-f2968697586f
+
 
diff --git a/dataset/bunny.dat b/dataset/bunny.dat
index 2608478..6ca9a37 100644
--- a/dataset/bunny.dat
+++ b/dataset/bunny.dat
@@ -1,129 +1,129 @@
 # x y nx ny 
-228.969 18.6691 -0.142503 -0.989794
-214.614 20.8804 -0.271324 -0.962488
-201.227 26.4899 -0.270028 -0.962853
-187.027 28.6103 -0.024168 -0.999708
-172.552 27.1909  0.119336 -0.992854
-158.155 25.1401 0.0932225 -0.995645
-143.624 24.4823 -0.0251171  -0.999685
-129.198 25.8689 -0.285292 -0.958441
-116.491 32.5679 -0.917162 -0.398515
-114.078 46.0523 -0.986312 -0.164892
-113.047 58.3086 -0.933771 -0.357872
-107.169 70.0382 -0.998194 0.0600762
-114.214 82.7168 -0.779438  0.626479
-124.976 92.1766 -0.533188  0.845997
-138.334 97.9326 -0.602708  0.797962
-146.754 108.722   -0.99998 0.00636636
-136.929 115.636 -0.410366 -0.911921
-122.925 119.605 -0.320878 -0.947121
-109.408  124.96 -0.482556 -0.875865
-97.7304  133.49 -0.619289 -0.785163
-86.6565 142.904  -0.69817 -0.715932
-76.9588 153.746 -0.856326 -0.516435
-67.5209 164.833 -0.824662 -0.565626
-  60.66 177.532 -0.827018 -0.562176
- 54.496 190.655 -0.962354 -0.271799
-49.2984 204.147 -0.982173  0.187981
-49.1295 218.672  -0.99896 0.0456026
-50.6214 233.132 -0.97224 0.233986
-55.1744 246.216 -0.976651 -0.214833
-44.1788 252.743 -0.525772 -0.850626
-32.4983 261.072  -0.75969 -0.650286
-24.9319 273.362 -0.952743  0.303779
- 23.986 287.768 -0.995882 0.0906624
-27.5213 301.856 -0.968207   0.25015
-31.2583 315.916 -0.977588  0.210529
-  33.64 330.268 -0.986761  0.162181
-35.9799 344.644 -0.999184 0.0403894
-34.8005  359.07 -0.993444  0.114323
-39.2236 372.802 -0.83245   0.5541
-50.1519 382.122 -0.505101   0.86306
-63.7849 387.189 -0.294318  0.955707
-77.9122 390.671 -0.251752  0.967792
-91.3056 394.351 -0.780164  0.625575
-92.7628 408.839 -0.994975  0.100121
-94.2209 423.323 -0.986009  0.166691
-97.5992 437.442 -0.935884  0.352308
-104.321 450.132 -0.704323  0.709879
-117.155 456.866 -0.210798   0.97753
-131.551 455.997 0.355984 0.934492
-144.143 448.292 0.844111 0.536168
-146.473 433.199   0.996914 -0.0785065
- 144.98 418.774  0.90178 0.432195
-139.837 405.185 0.516433 0.856328
-146.181 405.872 -0.234265  0.972173
-157.091  415.51 -0.29162 0.956534
-167.883 425.279 -0.652211  0.758038
-179.147 434.487 -0.608992  0.793177
-190.953 442.992 -0.560781  0.827964
-203.241 450.806 -0.535292  0.844667
-215.504  458.55 -0.548279  0.836296
-227.544 466.739 -0.545749  0.837949
-239.897 474.438 -0.41457 0.910017
-253.418 478.504 0.196699 0.980464
- 264.74 469.527 0.764407 0.644734
-271.739 456.915 0.822954 0.568108
-274.838 442.769   0.995683 -0.0928154
-274.414 428.243  0.969379 -0.245568
-267.912 415.501  0.783857 -0.620942
-256.868  406.07  0.559931 -0.828539
-243.988 399.333  0.437505 -0.899216
-230.716 393.346   0.40087 -0.916135
-217.332 387.669  0.431133 -0.902288
-204.507 380.823  0.469868 -0.882737
-191.649 373.998  0.491561 -0.870843
-179.188 366.531  0.530932 -0.847414
-167.035 358.577  0.824017 -0.566565
- 164.58 345.056   0.995925 -0.0901891
-169.426 331.373  0.998315 0.0580234
-178.374 319.982 0.574449  0.81854
-192.019 315.535 0.288952 0.957344
-206.017 311.637 0.273907 0.961756
-219.951  307.58  0.09506 0.995472
- 234.37 308.931 -0.169144  0.985591
-248.477 312.474 -0.24806 0.968745
-262.565 316.151 -0.243243  0.969965
-276.718 319.556 -0.204287  0.978911
-291.036 322.092 -0.121988  0.992532
-305.553 323.101 -0.0368414   0.999321
-320.104 323.164 0.0386137  0.999254
-334.569 321.979 0.214754 0.976668
-348.227 316.981 0.393408 0.919364
-361.282 310.548  0.47724 0.878773
-373.783 303.103 0.567348 0.823478
-385.183 294.081 0.659128  0.75203
-395.877 284.838 0.725596 0.688121
-404.893 272.733 0.742014 0.670385
- 413.06 260.701 0.832799 0.553575
-420.705 248.285 0.958039 0.286638
-425.819 234.605 0.852343 0.522983
- 431.05 220.008 0.978726 0.205173
-432.721 206.391  0.988524 -0.151062
-434.553 191.957    0.9943 -0.106623
-435.824 177.454   0.998241 -0.0592836
-436.265 163.099  0.68304 0.730381
-450.814 163.261 0.170737 0.985317
-464.132 158.249 0.605563 0.795797
-473.121 146.902 0.939887 0.341486
-474.213 132.334   0.999997 -0.0025838
-472.654 117.864  0.979425 -0.201807
-468.376 104.012 0.895933 -0.44419
-459.942 92.2238  0.748117 -0.663567
-449.223 82.4162  0.619113 -0.785302
-437.176  74.275  0.516586 -0.856235
-424.354 67.4126 0.427279 -0.90412
-410.904 61.8593  0.346664 -0.937989
-397.089 57.3358  0.299092 -0.954224
-383.158 53.1626  0.505331 -0.862926
-372.752 43.0794   0.65725 -0.753672
-361.382  34.173  0.458552 -0.888668
-347.475 30.0311  0.221991 -0.975049
-333.107 27.7349  0.133278 -0.991079
- 318.63 26.1521  0.101192 -0.994867
-304.152 24.7898  0.096887 -0.995295
-289.656 23.3317  0.103085 -0.994673
-275.184 21.7876  0.107156 -0.994242
-260.722 20.2132  0.105711 -0.994397
-246.242 18.7108 0.0588211 -0.998269
-231.711 18.5042 0.00632855   -0.99998
+271.031 481.331 -0.142503 -0.989794
+285.386  479.12 -0.271324 -0.962488
+298.773  473.51 -0.270028 -0.962853
+312.973  471.39 -0.024168 -0.999708
+327.448 472.809  0.119336 -0.992854
+341.845  474.86 0.0932226 -0.995645
+356.376 475.518 -0.0251171  -0.999685
+370.802 474.131 -0.285292 -0.958441
+383.509 467.432 -0.917162 -0.398515
+385.922 453.948 -0.986312 -0.164892
+386.953 441.691 -0.933771 -0.357872
+392.831 429.962 -0.998194 0.0600762
+385.786 417.283 -0.779438  0.626479
+375.024 407.823 -0.533188  0.845997
+361.666 402.067 -0.602708  0.797962
+353.246 391.278   -0.99998 0.00636636
+363.071 384.364 -0.410366 -0.911921
+377.075 380.395 -0.320878 -0.947121
+390.592  375.04 -0.482556 -0.875865
+402.27 366.51 -0.619289 -0.785163
+413.344 357.096  -0.69817 -0.715932
+423.041 346.254 -0.856326 -0.516435
+432.479 335.167 -0.824662 -0.565626
+ 439.34 322.468 -0.827018 -0.562176
+445.504 309.345 -0.962354 -0.271799
+450.702 295.853 -0.982173  0.187981
+450.871 281.328  -0.99896 0.0456026
+449.379 266.868 -0.97224 0.233986
+444.826 253.784 -0.976651 -0.214833
+455.821 247.257 -0.525772 -0.850626
+467.502 238.928  -0.75969 -0.650286
+475.068 226.638 -0.952743  0.303779
+476.014 212.232 -0.995882 0.0906624
+472.479 198.144 -0.968207   0.25015
+468.742 184.084 -0.977588  0.210529
+ 466.36 169.732 -0.986761  0.162181
+ 464.02 155.356 -0.999184 0.0403894
+ 465.2 140.93 -0.993444  0.114323
+460.777 127.198 -0.83245   0.5541
+449.848 117.878 -0.505101   0.86306
+436.215 112.811 -0.294318  0.955707
+422.088 109.329 -0.251752  0.967792
+408.695 105.649 -0.780164  0.625575
+407.237 91.1608 -0.994975  0.100121
+405.779 76.6768 -0.986009  0.166691
+402.401 62.5578 -0.935884  0.352308
+395.679 49.8678 -0.704323  0.709879
+382.845 43.1338 -0.210798   0.97753
+368.449 44.0028 0.355984 0.934492
+355.857 51.7078 0.844111 0.536168
+353.527 66.8008   0.996914 -0.0785065
+ 355.02 81.2258  0.90178 0.432195
+360.163 94.8148 0.516433 0.856328
+353.819 94.1278 -0.234265  0.972173
+342.909 84.4898 -0.29162 0.956534
+332.117 74.7208 -0.652211  0.758038
+320.853 65.5128 -0.608992  0.793177
+309.047 57.0078 -0.560781  0.827964
+296.759 49.1938 -0.535292  0.844667
+284.496 41.4498 -0.548279  0.836296
+272.456 33.2608 -0.545749  0.837949
+260.103 25.5618 -0.41457 0.910017
+246.582 21.4958 0.196699 0.980464
+ 235.26 30.4728 0.764407 0.644734
+228.261 43.0848 0.822954 0.568108
+225.162 57.2308   0.995683 -0.0928154
+225.586 71.7568  0.969379 -0.245568
+232.088 84.4988  0.783857 -0.620942
+243.132 93.9298  0.559931 -0.828539
+256.012 100.667  0.437505 -0.899216
+269.284 106.654   0.40087 -0.916135
+282.668 112.331  0.431133 -0.902288
+295.493 119.177  0.469868 -0.882737
+308.351 126.002  0.491561 -0.870843
+320.812 133.469  0.530932 -0.847414
+332.965 141.423  0.824017 -0.566565
+ 335.42 154.944   0.995925 -0.0901891
+330.574 168.627  0.998315 0.0580234
+321.626 180.018 0.574449  0.81854
+307.981 184.465 0.288952 0.957344
+293.983 188.363 0.273907 0.961756
+280.049  192.42  0.09506 0.995472
+ 265.63 191.069 -0.169144  0.985591
+251.523 187.526 -0.24806 0.968745
+237.435 183.849 -0.243243  0.969965
+223.282 180.444 -0.204287  0.978911
+208.964 177.908 -0.121988  0.992532
+194.447 176.899 -0.0368414   0.999321
+179.896 176.836 0.0386137  0.999254
+165.431 178.021 0.214754 0.976668
+151.773 183.019 0.393408 0.919364
+138.718 189.452  0.47724 0.878773
+126.217 196.897 0.567348 0.823478
+114.817 205.919 0.659128  0.75203
+104.123 215.162 0.725596 0.688121
+95.1071 227.267 0.742014 0.670385
+  86.94 239.299 0.832799 0.553575
+ 79.295 251.715 0.958039 0.286638
+ 74.181 265.395 0.852343 0.522983
+  68.95 279.992 0.978726 0.205173
+ 67.279 293.609  0.988524 -0.151062
+ 65.447 308.043    0.9943 -0.106623
+ 64.176 322.546   0.998241 -0.0592836
+ 63.735 336.901  0.68304 0.730381
+ 49.186 336.739 0.170737 0.985317
+ 35.868 341.751 0.605563 0.795797
+ 26.879 353.098 0.939887 0.341486
+ 25.787 367.666   0.999997 -0.0025838
+ 27.346 382.136  0.979425 -0.201807
+ 31.624 395.988 0.895933 -0.44419
+ 40.058 407.776  0.748117 -0.663567
+ 50.777 417.584  0.619113 -0.785302
+ 62.824 425.725  0.516586 -0.856235
+ 75.646 432.587 0.427279 -0.90412
+89.0961 438.141  0.346664 -0.937989
+102.911 442.664  0.299092 -0.954224
+116.842 446.837  0.505331 -0.862926
+127.248 456.921   0.65725 -0.753672
+138.618 465.827  0.458552 -0.888668
+152.525 469.969  0.221991 -0.975049
+166.893 472.265  0.133278 -0.991079
+ 181.37 473.848  0.101192 -0.994867
+195.848  475.21 0.0968871 -0.995295
+210.344 476.668  0.103085 -0.994673
+224.816 478.212  0.107156 -0.994242
+239.278 479.787  0.105711 -0.994397
+253.758 481.289  0.058821 -0.998269
+268.289 481.496 0.0063285  -0.99998
diff --git a/src/application.cpp b/src/application.cpp
index b9a4c7a..febf97c 100644
--- a/src/application.cpp
+++ b/src/application.cpp
@@ -28,7 +28,7 @@ const int tex_width = 500;
 const int tex_height = 500;
 
 PoncaPlotApplication::PoncaPlotApplication() :
-Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
+Screen(Vector2i(1200, 1024), "PoncaPlot"), m_dataMgr(new DataManager()){
 
     m_dataMgr->setKdTreePostUpdateFunction([this]() { this->renderPasses(); });
 
@@ -38,13 +38,14 @@ Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
     passOrientedSphereFit = new OrientedSphereFitField();
     passUnorientedSphereFit = new UnorientedSphereFitField();
 
-    m_passes[0] = new FillPass( {255,255,255,255});
-    m_passes[1] = passDFWithKdTree;
-    m_passes[2] = new DisplayPoint({255,0,0,255});
+    m_passes[0] = new FillPass( {1,1,1,1});
+    m_passes[1] = passOrientedSphereFit;
+    m_passes[2] = new ColorMap({1,1,1,1});
+    m_passes[3] = new DisplayPoint({0,0,0,1});
 
     inc_ref();
     auto *window = new Window(this, "Utils");
-    window->set_position(Vector2i(0, 0));
+    window->set_position(Vector2i(1000, 0));
     window->set_layout(new GroupLayout());
 
     // IO
@@ -73,10 +74,26 @@ Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
             const int bordersize = 20;
             m_dataMgr->fitPointCloudToRange({tex_width-bordersize, tex_height-bordersize},{bordersize,bordersize});
         });
+        b = new Button(tools, "Flip x");
+        b->set_callback([&] {
+            const int bordersize = 20;
+            for (auto& v : m_dataMgr->getPointContainer()){
+                v.x() = tex_width - v.x();
+            }
+            m_dataMgr->fitPointCloudToRange({tex_width-bordersize, tex_height-bordersize},{bordersize,bordersize});
+        });
+        b = new Button(tools, "Flip y");
+        b->set_callback([&] {
+            const int bordersize = 20;
+            for (auto& v : m_dataMgr->getPointContainer()){
+                v.y() = tex_height - v.y();
+            }
+            m_dataMgr->fitPointCloudToRange({tex_width-bordersize, tex_height-bordersize},{bordersize,bordersize});
+        });
     }
 
     window = new Window(this, "Fitting Controls");
-    window->set_position(Vector2i(0, 200));
+    window->set_position(Vector2i(0, 0));
     window->set_layout(new GroupLayout());
 
 
@@ -87,6 +104,7 @@ Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
                                         "Sphere",
                                         "Oriented Sphere",
                                         "Unoriented Sphere"});
+    combo->set_selected_index(3);
     combo->set_callback([this](int id){
         switch (id) {
             case 0: m_passes[1] = passDFWithKdTree; break;
@@ -110,7 +128,7 @@ Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
         // dunno why, but sets colorpicker in range [0-255], but reads in [0-1]
         auto cp = new ColorPicker(pass1Widget, (dynamic_cast<FillPass *>(m_passes[0]))->m_fillColor);
         cp->set_final_callback([this](const Color &c) {
-            dynamic_cast<FillPass *>(m_passes[0])->m_fillColor = 255.f * c;
+            dynamic_cast<FillPass *>(m_passes[0])->m_fillColor = c;
             renderPasses();
         });
     }
@@ -164,34 +182,74 @@ Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
     {
         pass3Widget = new nanogui::Widget(window);
         pass3Widget->set_layout(new GroupLayout());
-        new nanogui::Label(pass3Widget, "Points Display", "sans-bold");
-        new nanogui::Label(pass3Widget, "Color");
+        new nanogui::Label(pass3Widget, "Colormap", "sans-bold");
+        new nanogui::Label(pass3Widget, "0-iso color");
         // dunno why, but sets colorpicker in range [0-255], but reads in [0-1]
-        auto cp = new ColorPicker(pass3Widget, (dynamic_cast<DisplayPoint *>(m_passes[2]))->m_pointColor);
+        auto cp = new ColorPicker(pass3Widget, (dynamic_cast<ColorMap *>(m_passes[2]))->m_isoColor);
         cp->set_final_callback([this](const Color &c) {
-            dynamic_cast<DisplayPoint *>(m_passes[2])->m_pointColor = 255.f * c;
+            dynamic_cast<ColorMap *>(m_passes[2])->m_isoColor = c;
             renderPasses();
         });
+        new nanogui::Label(pass3Widget, "Default color");
+        cp = new ColorPicker(pass3Widget, (dynamic_cast<ColorMap *>(m_passes[2]))->m_defaultColor);
+        cp->set_final_callback([this](const Color &c) {
+            dynamic_cast<ColorMap *>(m_passes[2])->m_defaultColor = c;
+            renderPasses();
+        });
+        new nanogui::Label(pass3Widget, "Number of isolines");
+        auto int_box = new IntBox<int>(pass3Widget, dynamic_cast<ColorMap *>(m_passes[2])->m_isoQuantifyNumber);
+        int_box->set_editable(true);
+        int_box->set_spinnable(true);
+        int_box->set_min_value(1);
+        int_box->set_max_value(20);
+        int_box->set_value_increment(1);
+        int_box->set_callback([&](int value) {
+            dynamic_cast<ColorMap *>(m_passes[2])->m_isoQuantifyNumber = value;
+            renderPasses();
+        });
+
+        new nanogui::Label(pass3Widget, "0-isoline width");
         auto slider = new Slider(pass3Widget);
-        slider->set_value(dynamic_cast<DisplayPoint *>(m_passes[2])->m_halfSize);
+        slider->set_value(dynamic_cast<ColorMap *>(m_passes[2])->m_isoWidth);
+        slider->set_range({0.1,3.});
+        slider->set_callback([&](float value) {
+            dynamic_cast<ColorMap *>(m_passes[2])->m_isoWidth = value;
+            renderPasses();
+        });
+    }
+
+    // create pass 4 interface
+    {
+        pass4Widget = new nanogui::Widget(window);
+        pass4Widget->set_layout(new GroupLayout());
+        new nanogui::Label(pass4Widget, "Points Display", "sans-bold");
+        new nanogui::Label(pass4Widget, "Color");
+        // dunno why, but sets colorpicker in range [0-255], but reads in [0-1]
+        auto cp = new ColorPicker(pass4Widget, (dynamic_cast<DisplayPoint *>(m_passes[3]))->m_pointColor);
+        cp->set_final_callback([this](const Color &c) {
+            dynamic_cast<DisplayPoint *>(m_passes[3])->m_pointColor = c;
+            renderPasses();
+        });
+        auto slider = new Slider(pass4Widget);
+        slider->set_value(dynamic_cast<DisplayPoint *>(m_passes[3])->m_halfSize);
         slider->set_range({1,20});
         slider->set_callback([&](float value) {
-            dynamic_cast<DisplayPoint *>(m_passes[2])->m_halfSize = int(value);
+            dynamic_cast<DisplayPoint *>(m_passes[3])->m_halfSize = int(value);
             m_image_view->setSelectionThreshold(value);
             renderPasses();
         });
     }
 
     window = new Window(this, "Image");
-    window->set_position(Vector2i(200, 0));
+    window->set_position(Vector2i(210, 0));
     window->set_size(Vector2i(768,768));
     window->set_layout(new GroupLayout(3));
 
-    m_textureBufferPing = new uint8_t [tex_width * tex_height * 4]; // use UInt8 RGBA textures
-    m_textureBufferPong = new uint8_t [tex_width * tex_height * 4]; // use UInt8 RGBA textures
+    m_textureBufferPing = new float [tex_width * tex_height * 4]; // use Float32 RGBA textures
+    m_textureBufferPong = new float [tex_width * tex_height * 4]; // use Float32 RGBA textures
     m_texture = new Texture(
             Texture::PixelFormat::RGBA,
-            Texture::ComponentFormat::UInt8,
+            Texture::ComponentFormat::Float32,
             {tex_width,tex_height},
             Texture::InterpolationMode::Trilinear,
             Texture::InterpolationMode::Nearest,
@@ -203,11 +261,10 @@ Screen(Vector2i(1024, 768), "PoncaPlot"), m_dataMgr(new DataManager()){
     m_image_view->fitImage();
     m_image_view->center();
 
-    renderPasses(); // render twice to fill m_textureBufferPing and m_textureBufferPong
-    renderPasses();
+    buildPassInterface(3);
 
-    // call perform_layout
-    buildPassInterface(0);
+    renderPasses();
+    renderPasses(); // render twice to fill m_textureBufferPing and m_textureBufferPong
 }
 
 
@@ -231,7 +288,7 @@ PoncaPlotApplication::draw(NVGcontext *ctx) {
 void
 PoncaPlotApplication::draw_contents() {
     if (m_needUpdate){
-        m_texture->upload(m_computeInPing ? m_textureBufferPong : m_textureBufferPing);
+        m_texture->upload((const uint8_t*) (m_computeInPing ? m_textureBufferPong : m_textureBufferPing));
         m_needUpdate = false;
     }
     Screen::draw_contents();
diff --git a/src/application.h b/src/application.h
index 7c4b0d5..c95c87c 100644
--- a/src/application.h
+++ b/src/application.h
@@ -33,10 +33,10 @@ class PoncaPlotApplication : public nanogui::Screen {
 
     void renderPasses();
 private:
-    uint8_t*  m_textureBufferPing {nullptr}, *  m_textureBufferPong {nullptr};
+    float*  m_textureBufferPing {nullptr}, *  m_textureBufferPong {nullptr};
     bool m_computeInPing{true};
     nanogui::Texture*  m_texture {nullptr};
-    std::array<DrawingPass*,3> m_passes{nullptr, nullptr, nullptr};
+    std::array<DrawingPass*,4> m_passes{nullptr, nullptr, nullptr, nullptr}; // fill, compute, colormap, point
     bool m_needUpdate{false};
 
     DataManager *m_dataMgr{nullptr};
@@ -45,7 +45,7 @@ class PoncaPlotApplication : public nanogui::Screen {
     Widget* pass1Widget, *distanceFieldWidget,
             *genericFitWidget,    //< parameters applicable to all fitting techniques
     *planeFitWidget, *sphereFitWidget, *orientedSphereFitWidget, *unorientedSphereFitWidget,
-            *pass3Widget;
+            *pass3Widget,*pass4Widget;
     DistanceFieldWithKdTree *passDFWithKdTree;
     PlaneFitField *passPlaneFit;
     SphereFitField *passSphereFit;
diff --git a/src/drawingPass.h b/src/drawingPass.h
index b8e9d49..2000cd5 100644
--- a/src/drawingPass.h
+++ b/src/drawingPass.h
@@ -8,14 +8,14 @@
 
 /// Base class to rendering processes
 struct DrawingPass {
-    virtual void render(const DataManager::KdTree& points, uint8_t*buffer, int w, int h) = 0;
+    virtual void render(const DataManager::KdTree& points, float*buffer, int w, int h) = 0;
     virtual ~DrawingPass() = default;
 };
 
 struct FillPass : public DrawingPass {
-    inline explicit FillPass(const nanogui::Vector4i &fillColor = {255,255,255,255})
+    inline explicit FillPass(const nanogui::Vector4f &fillColor = {1,1,1,1})
             : m_fillColor(fillColor) {}
-    void render(const DataManager::KdTree& /*points*/, uint8_t*buffer, int w, int h) override{
+    void render(const DataManager::KdTree& /*points*/, float*buffer, int w, int h) override{
 #pragma omp parallel for default(none) shared(buffer, w, h)
         for(auto j = 0; j<w*h; ++j){
             buffer[j*4] = m_fillColor.x();
@@ -24,15 +24,15 @@ struct FillPass : public DrawingPass {
             buffer[j*4+3] = m_fillColor.w();
         }
     }
-    nanogui::Vector4i m_fillColor;
+    nanogui::Vector4f m_fillColor;
 };
 
 struct RandomPass : public DrawingPass {
     inline explicit RandomPass() : DrawingPass(), gen(rd()) {}
-    void render(const DataManager::KdTree& /*points*/, uint8_t*buffer, int w, int h) override{
+    void render(const DataManager::KdTree& /*points*/, float*buffer, int w, int h) override{
 #pragma omp parallel for default(none) shared(buffer, w, h)
         for(auto j = 0; j<w*h; ++j){
-            float grad = 255*float(j)/float(w*h);
+            float grad = float(j)/float(w*h);
             buffer[j*4] = grad;
             buffer[j*4+1] = grad;
             buffer[j*4+2] = grad;
@@ -47,9 +47,9 @@ struct RandomPass : public DrawingPass {
 };
 
 struct DisplayPoint : public DrawingPass {
-    inline explicit DisplayPoint(const nanogui::Vector4i &pointColor = {0,0,0,255})
+    inline explicit DisplayPoint(const nanogui::Vector4i &pointColor = {0,0,0,1})
             : DrawingPass(), m_pointColor(pointColor) {}
-    void render(const DataManager::KdTree& points, uint8_t*buffer, int w, int h) override{
+    void render(const DataManager::KdTree& points, float*buffer, int w, int h) override{
         using VectorType = typename DataManager::KdTree::VectorType;
         const auto pLargeSize = 2.f*m_halfSize;
 #pragma omp parallel for default(none) shared(points, buffer, w, h,pLargeSize)
@@ -85,6 +85,89 @@ struct DisplayPoint : public DrawingPass {
             }
         }
     }
-    nanogui::Vector4i m_pointColor;
+    nanogui::Vector4f m_pointColor;
     float m_halfSize{1.f};
 };
+
+
+/// Read the input texture and convert it to a color
+/// Expected input for scalar fields
+///   - R: value
+///   - G: max value for the entire image
+///   - B: 1 is value is valid, 0 otherwise (if 0, all fields the other are ignored)
+///   - A: 10 (recognition bit)
+///
+/// Pixels with invalid values are set to default color
+///
+/// \note The recognition bit and the max values are read from the first pixel (buffer[1] and buffer[3] respectively),
+///       and thus must be set even if the pixel is invalid
+struct ColorMap : public DrawingPass {
+    inline explicit ColorMap(const nanogui::Vector4i &isoColor = {1,1,1,1},
+                             const nanogui::Vector4i &defaultColor = {0,0,0,1})
+    : DrawingPass(), m_isoColor(isoColor), m_defaultColor(defaultColor) {}
+
+    [[nodiscard]] inline float quantify(float in) const
+    { return float(std::floor(in * float(m_isoQuantifyNumber)) / float(m_isoQuantifyNumber)); }
+
+    void render(const DataManager::KdTree& points, float*buffer, int w, int h) override{
+        const FieldType ftype {int(buffer[3])};
+        const auto maxVal = buffer[1];
+
+        if (ftype == NO_FIELD) return;
+
+#pragma omp parallel for default(none) shared(buffer, w, h, ftype, maxVal)
+        for(auto j = 0; j<w*h; ++j){
+            auto *b = buffer + j * 4;
+            auto val = b[0];
+            nanogui::Vector4f c =  m_defaultColor;
+
+            switch (ftype) {
+                case SCALAR_FIELD: {
+                    if( FieldValueType(b[2]) )
+                    {
+                        if(std::abs(val) < m_isoWidth)
+                        {
+                            c = m_isoColor;
+                        }
+                        else if(val > 0.f)
+                        {
+                            c[0] = quantify(1.f - val / maxVal);
+                            c[1] = 0;
+                            c[2] = 0;
+                        }
+                        else
+                        {
+                            c[0] = 0;
+                            c[1] = 0;
+                            c[2] = quantify(1.f - (-val / maxVal));
+                        }
+                        c[3] = 1;
+                    }
+
+                }
+                    break;
+                default:
+                    break;
+            }
+            b[0] = c.x();
+            b[1] = c.y();
+            b[2] = c.z();
+            b[3] = c.w();
+        }
+    }
+
+    int m_isoQuantifyNumber {10};
+    float m_isoWidth {0.8};
+    nanogui::Vector4f m_isoColor;
+    nanogui::Vector4f m_defaultColor;
+
+    enum FieldType: int {
+        SCALAR_FIELD = 10,
+        NO_FIELD
+    };
+
+    enum FieldValueType: bool {
+        VALUE_IS_VALID   = true,
+        VALUE_IS_INVALID = false
+    };
+};
diff --git a/src/drawingPasses/distanceField.h b/src/drawingPasses/distanceField.h
index cd7e049..d24b8b6 100644
--- a/src/drawingPasses/distanceField.h
+++ b/src/drawingPasses/distanceField.h
@@ -4,35 +4,45 @@
 
 struct DistanceField : public DrawingPass {
     inline explicit DistanceField() : DrawingPass() {}
-    void render(const DataManager::KdTree& points, uint8_t*buffer, int w, int h) override {
-        if(points.point_data().empty()) return;
+    void render(const DataManager::KdTree& points, float*buffer, int w, int h) override {
+        if(points.point_data().empty())
+        {
+            buffer[1] = ColorMap::NO_FIELD;
+            return;
+        }
 
-        const auto normFactor = float(std::max(w,h));
-#pragma omp parallel for collapse(2) default(none) shared(normFactor, points, buffer, w, h)
+        float maxVal = 0;
+#pragma omp parallel for collapse(2) default(none) shared(points, buffer, w, h) reduction(max : maxVal)
         for (int j = 0; j < h; ++j ) {
             for (int i = 0; i < w; ++i) {
                 auto *b = buffer + (i + j * w) * 4;
-                auto minDist = int(normFactor); //distance should necessarily be smaller
+                float minDist {float(w*h)};  //distance should necessarily be smaller
                 for (const auto &p : points.point_data()) {
                     int u(std::floor(p.pos().x()));
                     int v(std::floor(p.pos().y()));
-                    auto dist = int(std::sqrt((i-u)*(i-u) + (j-v)*(j-v)));
+                    auto dist = float(std::sqrt((i-u)*(i-u) + (j-v)*(j-v)));
                     minDist = std::min(dist, minDist);
                 }
-                auto col = int(255. * minDist / normFactor);
-                b[0] = b[1] = b[2] = col;
-                b[3] = 255;
+                b[0] = minDist;
+                b[2] = ColorMap::VALUE_IS_VALID;
+                b[3] = ColorMap::SCALAR_FIELD;
+                if (std::abs(minDist)> maxVal) maxVal = std::abs(minDist);
             }
         }
+        buffer[1] = maxVal;
     }
 };
 struct DistanceFieldWithKdTree : public DrawingPass {
     inline explicit DistanceFieldWithKdTree() : DrawingPass() {}
-    void render(const DataManager::KdTree& points, uint8_t*buffer, int w, int h) override{
-        if(points.point_data().empty()) return;
+    void render(const DataManager::KdTree& points, float*buffer, int w, int h) override{
+        if(points.point_data().empty())
+        {
+            buffer[1] = ColorMap::NO_FIELD;
+            return;
+        }
 
-        const auto normFactor = float(std::max(w,h));
-#pragma omp parallel for collapse(2) default(none) shared(normFactor, points, buffer, w, h)
+        float maxVal = 0;
+#pragma omp parallel for collapse(2) default(none) shared(points, buffer, w, h) reduction(max : maxVal)
         for (int j = 0; j < h; ++j ) {
             for (int i = 0; i < w; ++i) {
                 auto *b = buffer + (i + j * w) * 4;
@@ -41,11 +51,13 @@ struct DistanceFieldWithKdTree : public DrawingPass {
                 if(res.begin()!=res.end()) {
                     auto nei = points.point_data()[res.get()].pos();
                     float dist = (nei-query).norm();
-                    auto col = int (255. * dist / normFactor);
-                    b[0] = b[1] = b[2] = col;
-                    b[3] = 255;
+                    b[0] = dist;
+                    b[2] = ColorMap::VALUE_IS_VALID;
+                    b[3] = ColorMap::SCALAR_FIELD;
+                    if (std::abs(dist)> maxVal) maxVal = std::abs(dist);
                 }
             }
         }
+        buffer[1] = maxVal;
     }
 };
diff --git a/src/drawingPasses/poncaFitField.h b/src/drawingPasses/poncaFitField.h
index 2839c41..1c7806c 100644
--- a/src/drawingPasses/poncaFitField.h
+++ b/src/drawingPasses/poncaFitField.h
@@ -6,7 +6,7 @@
 struct BaseFitField : public DrawingPass{
     inline explicit BaseFitField() : DrawingPass() {}
     ~BaseFitField() override = default;
-    float m_scale {20.f};
+    float m_scale {40.f};
     int   m_iter  {1};
 };
 
@@ -19,11 +19,11 @@ struct FitField : public BaseFitField {
     using WeightFunc = typename FitType::WeightFunction;
 
 
-    void render(const DataManager::KdTree& points, uint8_t*buffer, int w, int h) override{
+    void render(const DataManager::KdTree& points, float*buffer, int w, int h) override{
         if(points.point_data().empty()) return;
 
-        const auto normFactor = float(std::max(w,h));
-#pragma omp parallel for collapse(2) default(none) shared(normFactor, points, buffer, w, h)
+        float maxVal = 0;
+#pragma omp parallel for collapse(2) default(none) shared(points, buffer, w, h) reduction(max : maxVal)
         for (int j = 0; j < h; ++j ) {
             for (int i = 0; i < w; ++i) {
                 auto *b = buffer + (i + j * w) * 4;
@@ -41,23 +41,19 @@ struct FitField : public BaseFitField {
                         query = fit.project(query);
                     }
                 }
-                if (fit.isStable()){
+
+                if ( (b[2] = fit.isStable()) ){
                     float dist = fit.potential({i,j});
-                    if (dist * dist < 1.4)
-                        b[0] = b[1] = b[2] = 255;
-                    else {
-                        auto col = int(255. * dist / m_scale);
-                        if (dist > 0)
-                            b[0] = b[1] = b[2] = col;
-                        else {
-                            b[0] = -col;
-                            b[1] = b[2] = 0;
-                        }
-                    }
-                    b[3] = 255;
+                    if (std::abs(dist)> maxVal) maxVal = std::abs(dist);
+
+                    b[0] = dist;                     // set pixel value
+                    b[3] = ColorMap::SCALAR_FIELD;   // set field type
                 }
             }
         }
+        // store data for colormap processing (see #ColorMap)
+        buffer[1] = maxVal;
+        buffer[3] = ColorMap::SCALAR_FIELD;
     }
 };