flower/Source/ImGui/ImGuiExtension.cpp

#include "ImGuiExtension.h"
#include "ImGuiInternal.h"

#include <stb/stb_image.h>
#include <glfw/glfw3.h>

namespace ImGui
{
	struct IconContext
	{
		GLFWimage images[1];
		IconContext()
		{
			images[0].pixels = stbi_load("Image/AppIcon.png", &images[0].width, &images[0].height, 0, 4);
		}
		~IconContext()
		{
			stbi_image_free(images[0].pixels);
		}
	};
	IconContext GIconContext{ };

	void ImGui::setWindowIcon(GLFWwindow* window)
	{
		glfwSetWindowIcon(window, 1, GIconContext.images);
	}

    static ImVector<ImRect> s_GroupPanelLabelStack;

    void ImGui::BeginGroupPanel(const char* name, const ImVec2& size)
    {
        ImGui::BeginGroup();


        auto cursorPos = ImGui::GetCursorScreenPos();
        auto itemSpacing = ImGui::GetStyle().ItemSpacing;
        ImGui::PushStyleVar(ImGuiStyleVar_FramePadding, ImVec2(0.0f, 0.0f));
        ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0.0f, 0.0f));

        auto frameHeight = ImGui::GetFrameHeight();
        ImGui::BeginGroup();

        ImVec2 effectiveSize = size;
        if (size.x < 0.0f)
            effectiveSize.x = ImGui::GetContentRegionAvail().x;
        else
            effectiveSize.x = size.x;
        ImGui::Dummy(ImVec2(effectiveSize.x, 0.0f));

        ImGui::Dummy(ImVec2(frameHeight * 0.5f, 0.0f));
        ImGui::SameLine(0.0f, 0.0f);
        ImGui::BeginGroup();
        ImGui::Dummy(ImVec2(frameHeight * 0.5f, 0.0f));
        ImGui::SameLine(0.0f, 0.0f);
        ImGui::TextUnformatted(name);
        auto labelMin = ImGui::GetItemRectMin();
        auto labelMax = ImGui::GetItemRectMax();
        ImGui::SameLine(0.0f, 0.0f);
        ImGui::Dummy(ImVec2(0.0, frameHeight + itemSpacing.y));
        ImGui::BeginGroup();

        //ImGui::GetWindowDrawList()->AddRect(labelMin, labelMax, IM_COL32(255, 0, 255, 255));

        ImGui::PopStyleVar(2);

        ImGui::GetCurrentWindow()->ContentRegionRect.Max.x -= frameHeight * 0.5f;
        ImGui::GetCurrentWindow()->WorkRect.Max.x -= frameHeight * 0.5f;
        ImGui::GetCurrentWindow()->InnerRect.Max.x -= frameHeight * 0.5f;
        ImGui::GetCurrentWindow()->Size.x -= frameHeight;

        auto itemWidth = ImGui::CalcItemWidth();
        ImGui::PushItemWidth(ImMax(0.0f, itemWidth - frameHeight));

        s_GroupPanelLabelStack.push_back(ImRect(labelMin, labelMax));
    }

    void ImGui::EndGroupPanel()
    {
        ImGui::PopItemWidth();

        auto itemSpacing = ImGui::GetStyle().ItemSpacing;

        ImGui::PushStyleVar(ImGuiStyleVar_FramePadding, ImVec2(0.0f, 0.0f));
        ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0.0f, 0.0f));

        auto frameHeight = ImGui::GetFrameHeight();

        ImGui::EndGroup();

        //ImGui::GetWindowDrawList()->AddRectFilled(ImGui::GetItemRectMin(), ImGui::GetItemRectMax(), IM_COL32(0, 255, 0, 64), 4.0f);

        ImGui::EndGroup();

        ImGui::SameLine(0.0f, 0.0f);
        ImGui::Dummy(ImVec2(frameHeight * 0.5f, 0.0f));
        ImGui::Dummy(ImVec2(0.0, frameHeight - frameHeight * 0.5f - itemSpacing.y));

        ImGui::EndGroup();

        auto itemMin = ImGui::GetItemRectMin();
        auto itemMax = ImGui::GetItemRectMax();
        //ImGui::GetWindowDrawList()->AddRectFilled(itemMin, itemMax, IM_COL32(255, 0, 0, 64), 4.0f);

        auto labelRect = s_GroupPanelLabelStack.back();
        s_GroupPanelLabelStack.pop_back();

        ImVec2 halfFrame = ImVec2(frameHeight * 0.25f * 0.5f, frameHeight * 0.5f);
        ImRect frameRect = ImRect(
            ImVec2{ itemMin.x + halfFrame.x, itemMin.y + halfFrame.y }, 
            ImVec2{ itemMax.x - halfFrame.x, itemMax.y });
        labelRect.Min.x -= itemSpacing.x;
        labelRect.Max.x += itemSpacing.x;
        for (int i = 0; i < 4; ++i)
        {
            switch (i)
            {
                // left half-plane
            case 0: ImGui::PushClipRect(ImVec2(-FLT_MAX, -FLT_MAX), ImVec2(labelRect.Min.x, FLT_MAX), true); break;
                // right half-plane
            case 1: ImGui::PushClipRect(ImVec2(labelRect.Max.x, -FLT_MAX), ImVec2(FLT_MAX, FLT_MAX), true); break;
                // top
            case 2: ImGui::PushClipRect(ImVec2(labelRect.Min.x, -FLT_MAX), ImVec2(labelRect.Max.x, labelRect.Min.y), true); break;
                // bottom
            case 3: ImGui::PushClipRect(ImVec2(labelRect.Min.x, labelRect.Max.y), ImVec2(labelRect.Max.x, FLT_MAX), true); break;
            }

            ImGui::GetWindowDrawList()->AddRect(
                frameRect.Min, frameRect.Max,
                ImColor(ImGui::GetStyleColorVec4(ImGuiCol_Border)),
                halfFrame.x);

            ImGui::PopClipRect();
        }

        ImGui::PopStyleVar(2);

        ImGui::GetCurrentWindow()->ContentRegionRect.Max.x += frameHeight * 0.5f;
        ImGui::GetCurrentWindow()->WorkRect.Max.x += frameHeight * 0.5f;
        ImGui::GetCurrentWindow()->InnerRect.Max.x += frameHeight * 0.5f;
        ImGui::GetCurrentWindow()->Size.x += frameHeight;

        ImGui::Dummy(ImVec2(0.0f, 0.0f));

        ImGui::EndGroup();
    }
}