Develop (#53)

* adding ruler tool and line drawing tool. closes: #50 ; closes: #49 
* shift-click to draw straight lines with brush tool. closes: #51 
* better keyboard handling (all dialogs can be confirmed/canceled using Return/Esc)
* toolbar can now be resized to have two columns

CMakeLists.txt

@@ -153,6 +153,8 @@ add_executable(HDRView
   src/commandhistory.h
   src/common.cpp
   src/common.h
+  src/dialog.cpp
+  src/dialog.h
   src/dithermatrix256.h
   src/drawline.cpp
   src/drawline.h

src/colorwheel.h

@@ -67,7 +67,7 @@ class ColorWheel2 : public Widget
     /// Handles mouse drag events for the ColorWheel.
     virtual bool mouse_drag_event(const Vector2i &p, const Vector2i &rel, int button, int modifiers) override;
 
-    /// Handle a mouse motion event (default implementation: propagate to children)
+    /// Handle a mouse motion event
     virtual bool mouse_motion_event(const Vector2i &p, const Vector2i &rel, int button, int modifiers) override;
 
 private:

src/dialog.cpp

@@ -0,0 +1,83 @@
+
+#include "dialog.h"
+#include <nanogui/button.h>
+#include <nanogui/formhelper.h>
+#include <nanogui/label.h>
+#include <nanogui/layout.h>
+
+NAMESPACE_BEGIN(nanogui)
+
+Dialog::Dialog(Widget *parent, const std::string &title, bool form) : Window(parent, title)
+{
+    set_modal(true);
+
+    request_focus();
+    if (form)
+        make_form();
+}
+
+void Dialog::make_form()
+{
+    // copied from FormHelper
+    auto layout = new AdvancedGridLayout({10, 0, 10, 0}, {});
+    layout->set_margin(10);
+    layout->set_col_stretch(2, 1);
+    set_layout(layout);
+}
+
+Widget *Dialog::add_buttons(const std::string &button_text, const std::string &alt_button_text, bool alt_button)
+{
+    Widget *button_panel = new Widget(this);
+    button_panel->set_layout(new GridLayout(Orientation::Horizontal, 2, Alignment::Fill, 0, 5));
+
+    if (alt_button)
+    {
+        Button *button = new Button(button_panel, alt_button_text, m_theme->m_message_alt_button_icon);
+        button->set_callback(
+            [this]
+            {
+                if (m_callback)
+                    m_callback(1);
+                dispose();
+            });
+    }
+    Button *button = new Button(button_panel, button_text, m_theme->m_message_primary_button_icon);
+    button->set_callback(
+        [this]
+        {
+            if (m_callback)
+                m_callback(0);
+            dispose();
+        });
+
+    return button_panel;
+}
+
+SimpleDialog::SimpleDialog(Widget *parent, Type type, const std::string &title, const std::string &message,
+                           const std::string &button_text, const std::string &alt_button_text, bool alt_button) :
+    Dialog(parent, title, false)
+{
+    set_layout(new BoxLayout(Orientation::Vertical, Alignment::Middle, 10, 10));
+
+    Widget *message_panel = new Widget(this);
+    message_panel->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 10, 15));
+    int icon = 0;
+    switch (type)
+    {
+    case Type::Empty: icon = 0; break;
+    case Type::Information: icon = m_theme->m_message_information_icon; break;
+    case Type::Question: icon = m_theme->m_message_question_icon; break;
+    case Type::Warning: icon = m_theme->m_message_warning_icon; break;
+    }
+    Label *icon_label = new Label(message_panel, std::string(utf8(icon).data()), "icons");
+    icon_label->set_font_size(50);
+    m_message_label = new Label(message_panel, message);
+    m_message_label->set_fixed_width(icon ? 200 : 0);
+
+    add_buttons(button_text, alt_button_text, alt_button);
+
+    center();
+    request_focus();
+}
+
+NAMESPACE_END(nanogui)

src/dialog.h

@@ -0,0 +1,50 @@
+
+#pragma once
+
+#include <nanogui/messagedialog.h>
+#include <nanogui/nanogui.h>
+
+NAMESPACE_BEGIN(nanogui)
+
+/// Similar to MessageDialog but extensible and can be used with FormHelper class
+class Dialog : public Window
+{
+public:
+    Dialog(Widget *parent, const std::string &title = "Untitled", bool form = true);
+
+    void    make_form();
+    Widget *add_buttons(const std::string &button_text = "OK", const std::string &alt_button_text = "Cancel",
+                        bool alt_button = true);
+
+    std::function<void(int)> callback() const { return m_callback; }
+    void                     set_callback(const std::function<void(int)> &callback) { m_callback = callback; }
+
+protected:
+    std::function<void(int)> m_callback;
+};
+
+/// Identical to MessageDialog but derived from the above Dialog class.
+class SimpleDialog : public Dialog
+{
+public:
+    /// Classification of the type of message this SimpleDialog represents.
+    enum class Type
+    {
+        Empty,
+        Information,
+        Question,
+        Warning
+    };
+
+    SimpleDialog(Widget *parent, Type type, const std::string &title = "Untitled",
+                 const std::string &message = "Message", const std::string &button_text = "OK",
+                 const std::string &alt_button_text = "Cancel", bool alt_button = false);
+
+    Label *      message_label() { return m_message_label; }
+    const Label *message_label() const { return m_message_label; }
+
+protected:
+    Label *m_message_label;
+};
+
+NAMESPACE_END(nanogui)