source/input/windows/touchscreen.cpp

   1 #define _WIN32_WINNT 0x0601
   2 #include <windows.h>
   3 #include <msp/graphics/window_private.h>
   4 #include "touchscreen.h"
   5
   6 using namespace std;
   7
   8 namespace Msp {
   9 namespace Input {
  10
  11 bool Touchscreen::is_available()
  12 {
  13         // Must have at least Windows 7 (WinNT 6.1) for WM_TOUCHMOVE
  14         OSVERSIONINFOEX version;
  15         version.dwOSVersionInfoSize = sizeof(version);
  16         version.dwMajorVersion = 6;
  17         version.dwMinorVersion = 1;
  18         version.wServicePackMajor = 0;
  19         version.wServicePackMinor = 0;
  20         DWORD mask = VER_MAJORVERSION|VER_MINORVERSION|VER_SERVICEPACKMAJOR|VER_SERVICEPACKMINOR;
  21         DWORDLONG cond = VerSetConditionMask(0, mask, VER_GREATER_EQUAL);
  22         if(VerifyVersionInfo(&version, mask, cond))
  23                 return false;
  24
  25         if(!GetSystemMetrics(SM_TABLETPC))
  26                 return false;
  27         if(!(GetSystemMetrics(SM_DIGITIZER)&NID_READY))
  28                 return false;
  29
  30         return true;
  31 }
  32
  33 void Touchscreen::input_event(const Graphics::Window::Event &event)
  34 {
  35         if(event.msg==WM_TOUCHMOVE)
  36         {
  37                 HTOUCHINPUT handle = reinterpret_cast<HTOUCHINPUT>(event.lparam);
  38                 unsigned n_points = LOWORD(event.wparam);
  39                 /* If I ever invent a legitimate use case for more touch points than an
  40                 average human has fingers, I'll come up with something else here. */
  41                 TOUCHINPUT touch_buffer[10];
  42                 if(!GetTouchInputInfo(handle, 10, touch_buffer, sizeof(TOUCHINPUT)))
  43                         return;
  44
  45                 for(unsigned i=0; i<n_points; ++i)
  46                 {
  47                         const TOUCHINPUT &point = touch_buffer[i];
  48
  49                         POINT screen_pt = { point.x/100, point.y/100 };
  50                         POINT client_pt = screen_pt;
  51                         ScreenToClient(window.get_private().window, &client_pt);
  52                         float x = (point.x/100.0f-screen_pt.x+client_pt.x)*2.0f/window.get_width()-1.0f;
  53                         float y = 1.0f-(point.y/100.0f-screen_pt.y+client_pt.y)*2.0f/window.get_height();
  54
  55                         touch_move(point.dwID, x, y);
  56                         if(point.dwFlags&TOUCHEVENTF_DOWN)
  57                                 touch_down(point.dwID);
  58                         else if(point.dwFlags&TOUCHEVENTF_UP)
  59                                 touch_up(point.dwID);
  60                 }
  61
  62                 CloseTouchInputHandle(handle);
  63         }
  64 }
  65
  66
  67
  68 } // namespace Input
  69 } // namespace Msp