text: // dear imgui: Renderer + Platform Binding for Marmalade + IwGx
  // Marmalade code: Copyright (C) 2015 by Giovanni Zito (this file is part of Dear ImGui)
  
  // Implemented features:
  //  [X] Renderer: User texture binding. Use 'CIwTexture*' as ImTextureID. Read the FAQ about ImTextureID!
  // Missing features:
  //  [ ] Renderer: Clipping rectangles are not honored.
  
  // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
  // If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
  // https://github.com/ocornut/imgui
  
  // CHANGELOG
  // (minor and older changes stripped away, please see git history for details)
  //  2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
  //  2019-05-11: Inputs: Don't filter value from character callback before calling AddInputCharacter().
  //  2018-11-30: Misc: Setting up io.BackendPlatformName/io.BackendRendererName so they can be displayed in the About Window.
  //  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_Marmalade_RenderDrawData() in the .h file so you can call it yourself.
  //  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
  //  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
  
  #include "imgui.h"
  #include "imgui_impl_marmalade.h"
  
  #include <s3eClipboard.h>
  #include <s3ePointer.h>
  #include <s3eKeyboard.h>
  #include <IwTexture.h>
  #include <IwGx.h>
  
  // Data
  static double       g_Time = 0.0f;
  static bool         g_MousePressed[3] = { false, false, false };
  static CIwTexture*  g_FontTexture = NULL;
  static char*        g_ClipboardText = NULL;
  static bool         g_osdKeyboardEnabled = false;
  
  // use this setting to scale the interface - e.g. on device you could use 2 or 3 scale factor
  static ImVec2       g_RenderScale = ImVec2(1.0f, 1.0f);
  
  // Render function.
  // (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop)
  void ImGui_Marmalade_RenderDrawData(ImDrawData* draw_data)
  {
      // Avoid rendering when minimized
      if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
          return;
  
      // Render command lists
      for (int n = 0; n < draw_data->CmdListsCount; n++)
      {
          const ImDrawList* cmd_list = draw_data->CmdLists[n];
          const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
          const int nVert = cmd_list->VtxBuffer.Size;
          CIwFVec2* pVertStream = IW_GX_ALLOC(CIwFVec2, nVert);
          CIwFVec2* pUVStream = IW_GX_ALLOC(CIwFVec2, nVert);
          CIwColour* pColStream = IW_GX_ALLOC(CIwColour, nVert);
  
          for (int i = 0; i < nVert; i++)
          {
              // FIXME-OPT: optimize multiplication on GPU using vertex shader/projection matrix.
              pVertStream[i].x = cmd_list->VtxBuffer[i].pos.x * g_RenderScale.x;
              pVertStream[i].y = cmd_list->VtxBuffer[i].pos.y * g_RenderScale.y;
              pUVStream[i].x = cmd_list->VtxBuffer[i].uv.x;
              pUVStream[i].y = cmd_list->VtxBuffer[i].uv.y;
              pColStream[i] = cmd_list->VtxBuffer[i].col;
          }
  
          IwGxSetVertStreamScreenSpace(pVertStream, nVert);
          IwGxSetUVStream(pUVStream);
          IwGxSetColStream(pColStream, nVert);
          IwGxSetNormStream(0);
  
          for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
          {
              const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
              if (pcmd->UserCallback)
              {
                  pcmd->UserCallback(cmd_list, pcmd);
              }
              else
              {
                  // FIXME: Not honoring ClipRect fields.
                  CIwMaterial* pCurrentMaterial = IW_GX_ALLOC_MATERIAL();
                  pCurrentMaterial->SetShadeMode(CIwMaterial::SHADE_FLAT);
                  pCurrentMaterial->SetCullMode(CIwMaterial::CULL_NONE);
                  pCurrentMaterial->SetFiltering(false);
                  pCurrentMaterial->SetAlphaMode(CIwMaterial::ALPHA_BLEND);
                  pCurrentMaterial->SetDepthWriteMode(CIwMaterial::DEPTH_WRITE_NORMAL);
                  pCurrentMaterial->SetAlphaTestMode(CIwMaterial::ALPHATEST_DISABLED);
                  pCurrentMaterial->SetTexture((CIwTexture*)pcmd->TextureId);
                  IwGxSetMaterial(pCurrentMaterial);
                  IwGxDrawPrims(IW_GX_TRI_LIST, (uint16*)idx_buffer, pcmd->ElemCount);
              }
              idx_buffer += pcmd->ElemCount;
          }
          IwGxFlush();
      }
  
      // TODO: restore modified state (i.e. mvp matrix)
  }
  
  static const char* ImGui_Marmalade_GetClipboardText(void* /*user_data*/)
  {
      if (!s3eClipboardAvailable())
          return NULL;
  
      if (int size = s3eClipboardGetText(NULL, 0))
      {
          if (g_ClipboardText)
              delete[] g_ClipboardText;
          g_ClipboardText = new char[size];
          g_ClipboardText[0] = '\0';
          s3eClipboardGetText(g_ClipboardText, size);
      }
  
      return g_ClipboardText;
  }
  
  static void ImGui_Marmalade_SetClipboardText(void* /*user_data*/, const char* text)
  {
      if (s3eClipboardAvailable())
          s3eClipboardSetText(text);
  }
  
  int32 ImGui_Marmalade_PointerButtonEventCallback(void* system_data, void* user_data)
  {
      // pEvent->m_Button is of type s3ePointerButton and indicates which mouse
      // button was pressed.  For touchscreen this should always have the value
      // S3E_POINTER_BUTTON_SELECT
      s3ePointerEvent* pEvent = (s3ePointerEvent*)system_data;
  
      if (pEvent->m_Pressed == 1)
      {
          if (pEvent->m_Button == S3E_POINTER_BUTTON_LEFTMOUSE)
              g_MousePressed[0] = true;
          if (pEvent->m_Button == S3E_POINTER_BUTTON_RIGHTMOUSE)
              g_MousePressed[1] = true;
          if (pEvent->m_Button == S3E_POINTER_BUTTON_MIDDLEMOUSE)
              g_MousePressed[2] = true;
          if (pEvent->m_Button == S3E_POINTER_BUTTON_MOUSEWHEELUP)
              io.MouseWheel += pEvent->m_y;
          if (pEvent->m_Button == S3E_POINTER_BUTTON_MOUSEWHEELDOWN)
              io.MouseWheel += pEvent->m_y;
      }
  
      return 0;
  }
  
  int32 ImGui_Marmalade_KeyCallback(void* system_data, void* user_data)
  {
      ImGuiIO& io = ImGui::GetIO();
      s3eKeyboardEvent* e = (s3eKeyboardEvent*)system_data;
      if (e->m_Pressed == 1)
          io.KeysDown[e->m_Key] = true;
      if (e->m_Pressed == 0)
          io.KeysDown[e->m_Key] = false;
  
      io.KeyCtrl = s3eKeyboardGetState(s3eKeyLeftControl) == S3E_KEY_STATE_DOWN || s3eKeyboardGetState(s3eKeyRightControl) == S3E_KEY_STATE_DOWN;
      io.KeyShift = s3eKeyboardGetState(s3eKeyLeftShift) == S3E_KEY_STATE_DOWN || s3eKeyboardGetState(s3eKeyRightShift) == S3E_KEY_STATE_DOWN;
      io.KeyAlt = s3eKeyboardGetState(s3eKeyLeftAlt) == S3E_KEY_STATE_DOWN || s3eKeyboardGetState(s3eKeyRightAlt) == S3E_KEY_STATE_DOWN;
      io.KeySuper = s3eKeyboardGetState(s3eKeyLeftWindows) == S3E_KEY_STATE_DOWN || s3eKeyboardGetState(s3eKeyRightWindows) == S3E_KEY_STATE_DOWN;
  
      return 0;
  }
  
  int32 ImGui_Marmalade_CharCallback(void* system_data, void* user_data)
  {
      ImGuiIO& io = ImGui::GetIO();
      s3eKeyboardCharEvent* e = (s3eKeyboardCharEvent*)system_data;
      io.AddInputCharacter((unsigned int)e->m_Char);
  
      return 0;
  }
  
  bool ImGui_Marmalade_CreateDeviceObjects()
  {
      // Build texture atlas
      ImGuiIO& io = ImGui::GetIO();
      unsigned char* pixels;
      int width, height;
      io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
  
      // Upload texture to graphics system
      g_FontTexture = new CIwTexture();
      g_FontTexture->SetModifiable(true);
      CIwImage& image = g_FontTexture->GetImage();
      image.SetFormat(CIwImage::ARGB_8888);
      image.SetWidth(width);
      image.SetHeight(height);
      image.SetBuffers();                                    // allocates and own buffers
      image.ReadTexels(pixels);
      g_FontTexture->SetMipMapping(false);
      g_FontTexture->SetFiltering(false);
      g_FontTexture->Upload();
  
      // Store our identifier
      io.Fonts->TexID = (ImTextureID)g_FontTexture;
  
      return true;
  }
  
  void    ImGui_Marmalade_InvalidateDeviceObjects()
  {
      if (g_ClipboardText)
      {
          delete[] g_ClipboardText;
          g_ClipboardText = NULL;
      }
  
      if (g_FontTexture)
      {
          delete g_FontTexture;
          ImGui::GetIO().Fonts->TexID = 0;
          g_FontTexture = NULL;
      }
  }
  
  bool    ImGui_Marmalade_Init(bool install_callbacks)
  {
      ImGuiIO& io = ImGui::GetIO();
      io.BackendPlatformName = io.BackendRendererName = "imgui_impl_marmalade";
  
      io.KeyMap[ImGuiKey_Tab] = s3eKeyTab;                     // Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array.
      io.KeyMap[ImGuiKey_LeftArrow] = s3eKeyLeft;
      io.KeyMap[ImGuiKey_RightArrow] = s3eKeyRight;
      io.KeyMap[ImGuiKey_UpArrow] = s3eKeyUp;
      io.KeyMap[ImGuiKey_DownArrow] = s3eKeyDown;
      io.KeyMap[ImGuiKey_PageUp] = s3eKeyPageUp;
      io.KeyMap[ImGuiKey_PageDown] = s3eKeyPageDown;
      io.KeyMap[ImGuiKey_Home] = s3eKeyHome;
      io.KeyMap[ImGuiKey_End] = s3eKeyEnd;
      io.KeyMap[ImGuiKey_Insert] = s3eKeyInsert;
      io.KeyMap[ImGuiKey_Delete] = s3eKeyDelete;
      io.KeyMap[ImGuiKey_Backspace] = s3eKeyBackspace;
      io.KeyMap[ImGuiKey_Space] = s3eKeySpace;
      io.KeyMap[ImGuiKey_Enter] = s3eKeyEnter;
      io.KeyMap[ImGuiKey_Escape] = s3eKeyEsc;
      io.KeyMap[ImGuiKey_KeyPadEnter] = s3eKeyNumPadEnter;
      io.KeyMap[ImGuiKey_A] = s3eKeyA;
      io.KeyMap[ImGuiKey_C] = s3eKeyC;
      io.KeyMap[ImGuiKey_V] = s3eKeyV;
      io.KeyMap[ImGuiKey_X] = s3eKeyX;
      io.KeyMap[ImGuiKey_Y] = s3eKeyY;
      io.KeyMap[ImGuiKey_Z] = s3eKeyZ;
  
      io.SetClipboardTextFn = ImGui_Marmalade_SetClipboardText;
      io.GetClipboardTextFn = ImGui_Marmalade_GetClipboardText;
  
      if (install_callbacks)
      {
          s3ePointerRegister(S3E_POINTER_BUTTON_EVENT, ImGui_Marmalade_PointerButtonEventCallback, 0);
          s3eKeyboardRegister(S3E_KEYBOARD_KEY_EVENT, ImGui_Marmalade_KeyCallback, 0);
          s3eKeyboardRegister(S3E_KEYBOARD_CHAR_EVENT, ImGui_Marmalade_CharCallback, 0);
      }
  
      return true;
  }
  
  void ImGui_Marmalade_Shutdown()
  {
      ImGui_Marmalade_InvalidateDeviceObjects();
  }
  
  void ImGui_Marmalade_NewFrame()
  {
      if (!g_FontTexture)
          ImGui_Marmalade_CreateDeviceObjects();
  
      ImGuiIO& io = ImGui::GetIO();
  
      // Setup display size (every frame to accommodate for window resizing)
      int w = IwGxGetScreenWidth(), h = IwGxGetScreenHeight();
      io.DisplaySize = ImVec2((float)w, (float)h);
      // For retina display or other situations where window coordinates are different from framebuffer coordinates. User storage only, presently not used by ImGui.
      io.DisplayFramebufferScale = g_scale;
  
      // Setup time step
      double current_time = s3eTimerGetUST() / 1000.0f;
      io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f / 60.0f);
      g_Time = current_time;
  
      double mouse_x, mouse_y;
      mouse_x = s3ePointerGetX();
      mouse_y = s3ePointerGetY();
      io.MousePos = ImVec2((float)mouse_x / g_scale.x, (float)mouse_y / g_scale.y); // Mouse position (set to -FLT_MAX,-FLT_MAX if no mouse / on another screen, etc.)
  
      for (int i = 0; i < 3; i++)
      {
          io.MouseDown[i] = g_MousePressed[i] || s3ePointerGetState((s3ePointerButton)i) != S3E_POINTER_STATE_UP;    // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
          g_MousePressed[i] = false;
      }
  
      // TODO: Hide OS mouse cursor if ImGui is drawing it
      // s3ePointerSetInt(S3E_POINTER_HIDE_CURSOR,(io.MouseDrawCursor ? 0 : 1));
  
      // Show/hide OSD keyboard
      if (io.WantTextInput)
      {
          // Some text input widget is active?
          if (!g_osdKeyboardEnabled)
          {
              g_osdKeyboardEnabled = true;
              s3eKeyboardSetInt(S3E_KEYBOARD_GET_CHAR, 1);    // show OSD keyboard
          }
      }
      else
      {
          // No text input widget is active
          if (g_osdKeyboardEnabled)
          {
              g_osdKeyboardEnabled = false;
              s3eKeyboardSetInt(S3E_KEYBOARD_GET_CHAR, 0);    // hide OSD keyboard
          }
      }
  }
  