From 46e4f54fd0d3962400947edd07777a309f6e8c75 Mon Sep 17 00:00:00 2001
From: YuSanka <yusanka@gmail.com>
Date: Wed, 31 Mar 2021 15:10:10 +0200
Subject: [PATCH] Auto color change: next improvements

---
 src/slic3r/GUI/DoubleSlider.cpp | 10 ++++++----
 src/slic3r/GUI/GUI_Preview.cpp  | 33 +++++++++++++++++++++++----------
 2 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/src/slic3r/GUI/DoubleSlider.cpp b/src/slic3r/GUI/DoubleSlider.cpp
index 94cfedbd4..29b488b90 100644
--- a/src/slic3r/GUI/DoubleSlider.cpp
+++ b/src/slic3r/GUI/DoubleSlider.cpp
@@ -719,7 +719,9 @@ wxString Control::get_label(int tick, LabelType label_type/* = ltHeightWithLayer
     // m_values contains data for all layer's parts,
     // but m_layers_values contains just unique Z values.
     // Use this function for correct conversion slider position to number of printed layer
-    auto get_layer_number = [this](int value) {
+    auto get_layer_number = [this](int value, LabelType label_type) {
+        if (label_type == ltEstimatedTime && m_layers_times.empty())
+            return size_t(-1);
         double layer_print_z = m_values[is_wipe_tower_layer(value) ? std::max<int>(value - 1, 0) : value];
         auto it = std::lower_bound(m_layers_values.begin(), m_layers_values.end(), layer_print_z - epsilon());
         if (it == m_layers_values.end()) {
@@ -744,7 +746,7 @@ wxString Control::get_label(int tick, LabelType label_type/* = ltHeightWithLayer
     else {
         if (label_type == ltEstimatedTime) {
             if (m_is_wipe_tower) {
-                size_t layer_number = get_layer_number(value);
+                size_t layer_number = get_layer_number(value, label_type);
                 return layer_number == size_t(-1) ? "" : short_and_splitted_time(get_time_dhms(m_layers_times[layer_number]));
             }
             return value < m_layers_times.size() ? short_and_splitted_time(get_time_dhms(m_layers_times[value])) : "";
@@ -755,7 +757,7 @@ wxString Control::get_label(int tick, LabelType label_type/* = ltHeightWithLayer
         if (label_type == ltHeight)
             return str;
         if (label_type == ltHeightWithLayer) {
-            size_t layer_number = m_is_wipe_tower ? get_layer_number(value) : (m_values.empty() ? value : value + 1);
+            size_t layer_number = m_is_wipe_tower ? get_layer_number(value, label_type) : (m_values.empty() ? value : value + 1);
             return format_wxstr("%1%\n(%2%)", str, layer_number);
         }
     }
@@ -2036,7 +2038,7 @@ void Control::auto_color_change()
             Layer* layer = object->get_layer(i);
             double cur_area = area(layer->lslices);
 
-            if (cur_area > prev_area)
+            if (cur_area > prev_area && prev_area - cur_area > scale_(scale_(1)))
                 break;
 
             if (prev_area - cur_area > delta_area) {
diff --git a/src/slic3r/GUI/GUI_Preview.cpp b/src/slic3r/GUI/GUI_Preview.cpp
index 5e2f8e8ed..e67ddb045 100644
--- a/src/slic3r/GUI/GUI_Preview.cpp
+++ b/src/slic3r/GUI/GUI_Preview.cpp
@@ -652,24 +652,37 @@ void Preview::update_layers_slider(const std::vector<double>& layers_z, bool kee
 
         //bool is_possible_auto_color_change = false;
         for (auto object : print.objects()) {
-            // bottom layer have to be a biggest, so control relation between bottom lazer and object size
-            const ExPolygons& bottom = object->get_layer(0)->lslices;
-            double bottom_area = area(bottom);
-            if (bottom_area < double(object->size().x()) * double(object->size().y()))
-                continue;
+            double object_x = double(object->size().x());
+            double object_y = double(object->size().y());
 
             // if it's sign, than object have not to be a too height
             double height = object->height();
-            coord_t longer_side = std::max(object->size().x(), object->size().y());
+            coord_t longer_side = std::max(object_x, object_y);
             if (height / longer_side > 0.3)
                 continue;
 
+            const ExPolygons& bottom = object->get_layer(0)->lslices;
+            double bottom_area = area(bottom);
+
             // at least 30% of object's height have to be a solid 
-            int i;
-            for (i = 1; i < int(0.3 * object->layers().size()); i++)
-                if (area(object->get_layer(1)->lslices) != bottom_area)
+            size_t i;
+            for (i = 1; i < size_t(0.3 * object->layers().size()); i++) {
+                double cur_area = area(object->get_layer(i)->lslices);
+                if (cur_area != bottom_area && fabs(cur_area - bottom_area) > scale_(scale_(1)))
                     break;
-            if (i < int(0.3 * object->layers().size()))
+            }
+            if (i < size_t(0.3 * object->layers().size()))
+                continue;
+
+            // bottom layer have to be a biggest, so control relation between bottom layer and object size
+            double prev_area = area(object->get_layer(i)->lslices);
+            for ( i++; i < object->layers().size(); i++) {
+                double cur_area = area(object->get_layer(i)->lslices);
+                if (cur_area > prev_area && prev_area - cur_area > scale_(scale_(1)))
+                    break;
+                prev_area = cur_area;
+            }
+            if (i < object->layers().size())
                 continue;
 
             double top_area = area(object->get_layer(int(object->layers().size()) - 1)->lslices);