Implement SDF fonts. (#24)

* Initial SDF font generation work.

* Text now correctly displaying with proper spacing.

* Fix untextured draws, implement custom rectangles.

* Fix regular image display.

* Slightly refactor ImGui rendering.

* Implement outlines.

* Implement bevel.

* Create host device after loading the module if the installer wasn't run.

* Move ImGui files to its own folder.

* Fix outline sizes.

* Fix default ImGui font and font scales.

* Update font atlas files.

UnleashedRecomp/gpu/imgui/imgui_common.cpp

@@ -0,0 +1,22 @@
+#include "imgui_common.h"
+
+static std::vector<std::unique_ptr<ImGuiCallbackData>> g_callbackData;
+static uint32_t g_callbackDataIndex = 0;
+
+ImGuiCallbackData* AddImGuiCallback(ImGuiCallback callback)
+{
+    if (g_callbackDataIndex >= g_callbackData.size())
+        g_callbackData.emplace_back(std::make_unique<ImGuiCallbackData>());
+
+    auto& callbackData = g_callbackData[g_callbackDataIndex];
+    ++g_callbackDataIndex;
+
+    ImGui::GetForegroundDrawList()->AddCallback(reinterpret_cast<ImDrawCallback>(callback), callbackData.get());
+
+    return callbackData.get();
+}
+
+void ResetImGuiCallbacks()
+{
+    g_callbackDataIndex = 0;
+}