sdl/PlatformKeyboard.cpp

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//* -*- mode:C++; tab-width:4; c-basic-offset:4; indent-tabs-mode:nil -*- */
//    Name:       src/platforms/sdl/Keyboard.cpp
//    Purpose:    Contains SDL-specific interface for the keyboard handler
//    Author:     Shane T. Mueller, Ph.D.
//    Copyright:  (c) 2003-2026 Shane T. Mueller <smueller@obereed.net>
//    License:    GPL 2
//
//
//
//     This file is part of the PEBL project.
//
//    PEBL is free software; you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation; either version 2 of the License, or
//    (at your option) any later version.
//
//    PEBL is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU General Public License for more details.
//
//    You should have received a copy of the GNU General Public License
//    along with PEBL; if not, write to the Free Software
//    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#include "PlatformKeyboard.h"
#include "../../devices/PKeyboard.h"
#include "../../devices/DeviceState.h"
 
 
#include "PlatformTimer.h"
 
 
#include "SDL.h"
#include <stdio.h>
 
// cout removed - use cerr for debug output
using std::cerr;
using std::endl;
using std::flush;
using std::list;
using std::ostream;
 
 
 
 
 
 
PlatformKeyboard::PlatformKeyboard()
    //    mCDT(CDT_KEYBOARD)
{
 
    //EMSCRIPTEN uses sdl 2, which replaces getkeystat with getkeyboardstate
#if defined PEBL_EMSCRIPTEN
    mKeyboardState = SDL_GetKeyboardState(NULL);  
    SDL_PumpEvents();
#else
    mKeyboardState = SDL_GetKeyboardState(NULL);
    SDL_PumpEvents();
#endif
}
 
 
PlatformKeyboard::~PlatformKeyboard()
{
 
}
 
 
//We can distinguish between scancodes and keycodes!
//scancode is an absolute keyboard position.
 
PEBL_Keycode PlatformKeyboard::IsKeyDown(PEBL_Keycode key) const
{
    if(key == PEBL_KEYCODE_ANYKEY)
        {
 
 
            return IsAnyKeyDown();
        }
    else
        {
 
 
            SDL_PumpEvents();   
            if( mKeyboardState[key] == 1)
                return key;
            else
                return PEBL_KEYCODE_NOTHING;
 
        }
}
 
 
 
 
bool PlatformKeyboard::IsKeyUp(PEBL_Keycode key) const
{
 
    //cout << "Testing for iskeyup: " << key << "|" << PEBL_KEYCODE_ANYKEY << endl;
        
        //If the key is 'anykey', what you are really asking is if there
    //are any keys that are not up. This is a semantic distortion, because
    //logically, you should be asking whether ALL keys are pressed, which
    //is pretty ridiculous.
    //
    if(key == PEBL_KEYCODE_ANYKEY)
        {
            PEBL_Keycode key = IsAnyKeyDown();
 
            return key;
        }
    else
        {
            //SDL_PumpEvents();
            //cout << "Getting scancode name  from key: " << key << endl;
            int code = SDL_GetScancodeFromKey(key);
            //cout << code << "---------" << endl;
            if(mKeyboardState[code]==1)
                return key;
            else
                return PEBL_KEYCODE_NOTHING; //==0==false
        }
}
 
   
PEBL_Keycode PlatformKeyboard::IsAnyKeyDown() const
{
 
 
    int code = 0;
 
    //Update the keyboard state from SDL function.
    //SDL_PumpEvents();
 
 
    //    int    keys;
    //    const Uint8 *state  = SDL_GetKeyboardState(&keys);
    //    //this justdisplays the completekeyboardstate.
    //    for(int i = 0;i<keys;i++)
    //            {
    //                cout <<"|"<< i<< ":" << state[i] << std::flush;
    //            }
    //    cout << endl;
 
    
    //Skip uppercase letters: do standard letters
    for(int i = 91; i<=127; i++)
        {
            
            if(mKeyboardState[i]) code=i;
        }
    
    //Go through first 64
    for(int i = 0; i<=64; i++)
        {
 
            if(mKeyboardState[i]) code =i;
        }
    
    
    //Keypad, function keys, etc.
    for(int i = 256; i<=296; i++)
        {
 
            if(mKeyboardState[i]) code = i;
        }
    
    
    
    //Modkeys/misc
    for(int i = 300; i<=322; i++)
        {
 
            if(mKeyboardState[i]) code = i;
        }
 
  
   //International letters (out of order, but of lower priority)
    for(int i = 160; i<=255; i++)
        {
 
            if(mKeyboardState[i]) code = i;
        }
 
 
    if(code==0)
        return PEBL_KEYCODE_NOTHING;
    else
        return  (PEBL_Keycode)SDL_GetKeyFromScancode((SDL_Scancode)code);
 
}
 
 
int PlatformKeyboard::GetState(int iface) const
{
 
    //This asks for the state of a particular key.
 
 
    PEBL_Keycode key = (PEBL_Keycode)iface;
    int ret = (int)IsKeyUp(key);
    
    //cout << "keyboard Getstating: " <<    PEBL_KEYCODE_x <<":"<<iface <<"|" << ret << endl;
    return ret;
}
 
 
 
 
 
 
// Inheritable function that is called by friend method << operator of PComplexData
ostream & PlatformKeyboard::SendToStream(ostream& out) const
{
    
    out << "<SDL PlatformKeyboard>" << flush;
    return out;
}