imgui_tabs

Tab module for imgui. Should be relatively forwardly compatible.

Code like this:

ImGui::BeginTabBar("Settings#left_tabs_bar");

// ericb 2017_07_21 : draw the tabs background BEFORE to fill it, to avoid a "colored overlay"
ImGui::DrawTabsBackground();

if (ImGui::AddTab("General")){
    bool fullscreen = mGUICfg->fullScreen.value;
    if(ImGui::Checkbox("Fullscreen Mode",&fullscreen)){
        mGUICfg->toggleFullscreenMode = true;
    }
    if(ImGui::Checkbox("Enable Multisampling",&mGUICfg->enableMultisampling.value)){
        mGUICfg->settingsChanged = true;
    }

    if(ImGui::SliderInt("MSAA Count",(int*)&mGUICfg->multisampleCount.value,mGUICfg->multisampleCount.lowerLimit,mGUICfg->multisampleCount.upperLimit))
        mGUICfg->settingsChanged = true;
}
if (ImGui::AddTab("GUI")){
    ImGui::Text("Tab 2");
}
if (ImGui::AddTab("Tab Name")){
    ImGui::Text("Tab 3");
}
if (ImGui::AddTab("Tab Name")){
    ImGui::Text("Tab 4");
}
ImGui::EndTabBar();

ImGui::Dummy(ImVec2(0,20));

ImGui::BeginTabBar("#Additional Parameters");
float value = 0.0f;

// ericb 2017_07_21 : draw the tabs background BEFORE to fill it, to avoid a "colored overlay"
ImGui::DrawTabsBackground();

if (ImGui::AddTab("Tab Name2")){
    ImGui::SliderFloat("Slider",&value,0,1.0f);
}
if (ImGui::AddTab("Tab Name3")){
    ImGui::Text("Tab 2");
}
if (ImGui::AddTab("Tab Name4")){
    ImGui::Text("Tab 3");
}
if (ImGui::AddTab("Tab Name5")){
    ImGui::Text("Tab 4");
}
ImGui::EndTabBar();

Yields results like this:

Usage:

 To start a tab bar, use: ImGui::BeginTabBar(const char* label)
      -> The label can be blank if you want, but you MUST!! pass a string of some length. Use the '#' character to
          give it an ID without a label.

  Add tabs by using:
      if (ImGui::AddTab("Tab Name")){
             < Insert other draw commands here >
      }
      -> This is much like collapsing header. If the tab is active, then AddTab will return true, allowing drawing
          to occur.

  End the tab bar by using ImGui::EndTabBar()

  And that's it! You can dynamically add or remove tabs, the bar will reset the ID and tab label vectors appropriately,
  but it DOESN'T continuously allocate/deallocate them in memory every time (unless the CRC32 hashes of the tab or tab bar change,
  computed from their respective labels).

  Notes:
      * You can change the rounding by altering:
              "static constexpr const float rounding = 6.0f;"
         in the _drawTabBarTop function. Alternatively, you can add it as a parameter, but to save on memory being passed
         around, and since I will be using 6 as a constant, I didn't include this.

      * The constexpr:
              "static constexpr const float shrink = 1.0f;"
         in the _drawTabBarTop function needs to be set to the width of your borders.

      * I added custom colors and a new prototype for GetColorU32() to acquire these colors. You can change them here.

      * I added extra operator functions for ImVec2 and ImVec4, _YOU MUST_ define IMGUI_DEFINE_MATH_OPERATORS in
         imgui_internal.h for this to work.

      * Please attribute my work if used or added, along with the original ImGui license/attribution.