Full standalone dinput8 / Direct Input example

[kung foo man]

Have fun, took me some hours. I ripped the code mostly from here, but extended/ordered it, so it's more useful (e.g. get all Virtual Key/VK codes): http://www.rastertek.com/dx11tut13.html

AND... that example code had an important filthy error, which took me some hours to realize why the heck nothing works:


result = m_keyboard->GetDeviceState(sizeof(m_keyboardState), (LPVOID)&m_keyboardState);

Correct (without &, since it's already an array/address):


result = m_keyboard->GetDeviceState(sizeof(m_keyboardState), (LPVOID)m_keyboardState);

So here is the full source as standalone working example, just drop it in Visual Studio:



#include <Windows.h>
#include <winnt.h>
#include <stdio.h>

//https://blogs.msdn.microsoft.com/oldnewthing/20041025-00/?p=37483
//http://stackoverflow.com/questions/1749972/determine-the-current-hinstance
EXTERN_C IMAGE_DOS_HEADER __ImageBase;
#define HINST_THISCOMPONENT ((HINSTANCE)&__ImageBase)

#include <dinput.h>
class DirectInput {
public:
IDirectInput8* m_directInput;
IDirectInputDevice8* m_keyboard;
IDirectInputDevice8* m_mouse;
DIMOUSESTATE m_mouseState;
DirectInput();
int init();
bool ReadMouse();
unsigned char m_keyboardState[256];
bool ReadKeyboard();
};

DirectInput *directinput = NULL;

DirectInput::DirectInput() {

}

int DirectInput::init() {
// Initialize the main direct input interface.
int result = DirectInput8Create(HINST_THISCOMPONENT, DIRECTINPUT_VERSION, IID_IDirectInput8, (void**)&m_directInput, NULL);
if(FAILED(result)) {
return 0;
}

//The first input device we will initialize will be the keyboard.

// Initialize the direct input interface for the keyboard.
result = m_directInput->CreateDevice(GUID_SysKeyboard, &m_keyboard, NULL);
if(FAILED(result))
{
return false;
}

// Set the data format. In this case since it is a keyboard we can use the predefined data format.
result = m_keyboard->SetDataFormat(&c_dfDIKeyboard);
if(FAILED(result))
{
return false;
}
//Setting the cooperative level of the keyboard is important in both what it does and how you use the device from that point forward. In this case we will set it to not share with other programs (DISCL_EXCLUSIVE). This way if you press a key only your application can see that input and no other application will have access to it. However if you want other applications to have access to keyboard input while your program is running you can set it to non-exclusive (DISCL_NONEXCLUSIVE). Now the print screen key works again and other running applications can be controlled by the keyboard and so forth. Just remember that if it is non-exclusive and you are running in a windowed mode then you will need to check for when the device loses focus and when it re-gains that focus so it can re-acquire the device for use again. This focus loss generally happens when other windows become the main focus over your window or your window is minimized.

//Set the cooperative level of the keyboard to not share with other programs.
//HWND hwnd = GetActiveWindow();
//result = m_keyboard->SetCooperativeLevel(hwnd, DISCL_BACKGROUND | DISCL_NONEXCLUSIVE);
////result = m_keyboard->SetCooperativeLevel(hwnd, DISCL_FOREGROUND | DISCL_EXCLUSIVE);
//if(FAILED(result))
//{
// return false;
//}
//Once they keyboard is setup we then call Acquire to finally get access to the keyboard for use from this point forward.

// Now acquire the keyboard.
result = m_keyboard->Acquire();
if(FAILED(result))
{
return false;
}

// Initialize the direct input interface for the mouse.
result = m_directInput->CreateDevice(GUID_SysMouse, &m_mouse, NULL);
if(FAILED(result))
{
return 0;
}

// Set the data format for the mouse using the pre-defined mouse data format.
result = m_mouse->SetDataFormat(&c_dfDIMouse);
if(FAILED(result)) {
return 0;
}

// MOUSE
//We use non-exclusive cooperative settings for the mouse. We will have to check for when it goes in and out of focus and re-acquire it each time.
// Set the cooperative level of the mouse to share with other programs.
//HWND hwnd = GetActiveWindow();
//result = m_mouse->SetCooperativeLevel(hwnd, DISCL_FOREGROUND | DISCL_NONEXCLUSIVE);
//if(FAILED(result))
//{
// return 0;
//}

result = m_mouse->Acquire();
if(FAILED(result)) {
return 0;
}
//Sys_Printf("got the mouse!\n");
}
bool DirectInput::ReadKeyboard() {
HRESULT result;
memset(m_keyboardState, 0, 256); // probably not needed, but who knows
result = m_keyboard->GetDeviceState(sizeof(m_keyboardState), (LPVOID)m_keyboardState);
if(FAILED(result)) {
printf("failed ReadKeyboard()\n");
// If the keyboard lost focus or was not acquired then try to get control back.
if((result == DIERR_INPUTLOST) || (result == DIERR_NOTACQUIRED)) {
m_keyboard->Acquire();
} else {
return false;
}
}
return true;
}

bool DirectInput::ReadMouse() {
HRESULT result;
result = m_mouse->GetDeviceState(sizeof(DIMOUSESTATE), (LPVOID)&m_mouseState);
if(FAILED(result)) {
// If the mouse lost focus or was not acquired then try to get control back.
if((result == DIERR_INPUTLOST) || (result == DIERR_NOTACQUIRED)) {
m_mouse->Acquire();
} else {
return false;
}
}
return true;
}

int main() {
directinput = new DirectInput();
directinput->init();
while(1) {
int ret = directinput->ReadKeyboard();
if(!ret)
continue;

int keys_pressed = 0;
for(int i = 0; i < 256; i++) {
if((directinput->m_keyboardState[i] & 128) == 0)
continue;
unsigned char scancode = i;
UINT key = MapVirtualKey(scancode, MAPVK_VSC_TO_VK_EX);
//UINT key = MapVirtualKeyEx(scancode, MAPVK_VSC_TO_VK, GetKeyboardLayout(0)); // same as MapVirtualKey

switch(scancode) {
case 203: key = VK_LEFT; break;
case 205: key = VK_RIGHT; break;
case 200: key = VK_UP; break;
case 208: key = VK_DOWN; break;
case 211: key = VK_DELETE; break;
case 207: key = VK_END; break;
case 199: key = VK_HOME; break; // pos1
case 201: key = VK_PRIOR; break; // page up
case 209: key = VK_NEXT; break; // page down
case 210: key = VK_INSERT; break;
case 184: key = VK_RMENU; break; // right alt
case 157: key = VK_RCONTROL; break; // right control
case 219: key = VK_LWIN; break; // left win
case 220: key = VK_RWIN; break; // right win
case 156: key = VK_RETURN; break; // right enter
case 181: key = VK_DIVIDE; break; // numpad divide
case 221: key = VK_APPS; break; // menu key
}

printf("keys_pressed=%d scancode=%d/0x%x key=%d char=%c hex=0x%x\n", keys_pressed, scancode, scancode, key, key, key);
keys_pressed++;
}

Sleep((int)(1000.0 / 60.0));
}
return 0;
}