// DEMO13_11.CPP - Time based motion modeling
// to compile make sure to include DDRAW.LIB, DSOUND.LIB,
// DINPUT.LIB, WINMM.LIB, and of course the T3DLIB files

// INCLUDES ///////////////////////////////////////////////

#define INITGUID

#define WIN32_LEAN_AND_MEAN  

#include <windows.h>   // include important windows stuff
#include <windowsx.h> 
#include <mmsystem.h>
#include <iostream.h> // include important C/C++ stuff
#include <conio.h>
#include <stdlib.h>
#include <malloc.h>
#include <memory.h>
#include <string.h>
#include <stdarg.h>
#include <stdio.h> 
#include <math.h>
#include <io.h>
#include <fcntl.h>

#include <ddraw.h>  // directX includes
#include <dsound.h>
#include <dmksctrl.h>
#include <dmusici.h>
#include <dmusicc.h>
#include <dmusicf.h>
#include <dinput.h>
#include "T3DLIB1.h" // game library includes
#include "T3DLIB2.h"
#include "T3DLIB3.h"

// DEFINES ////////////////////////////////////////////////

// defines for windows 
#define WINDOW_CLASS_NAME "WINXCLASS"  // class name

#define WINDOW_WIDTH    320  // size of window
#define WINDOW_HEIGHT   240

// variable indices
#define SHIP_X_POS  0
#define SHIP_Y_POS  1
#define SHIP_X_VEL  2

#define SHIP_INITIAL_VELOCITY   0.050    // 50 pixels/sec

// MACROS ///////////////////////////////////////////////

#define RAND_RANGE(x,y) ( (x) + (rand()%((y)-(x)+1)))
#define DOT_PRODUCT(ux,uy,vx,vy) ((ux)*(vx) + (uy)*(vy))

// PROTOTYPES /////////////////////////////////////////////

// game console
int Game_Init(void *parms=NULL);
int Game_Shutdown(void *parms=NULL);
int Game_Main(void *parms=NULL);

// GLOBALS ////////////////////////////////////////////////

HWND main_window_handle   = NULL; // save the window handle
HINSTANCE main_instance   = NULL; // save the instance
char buffer[256];                 // used to print text

BITMAP_IMAGE background_bmp;      // holds the background
BOB          ship;                // the ship

int engine_id = -1;              // sound of engine

// FUNCTIONS //////////////////////////////////////////////

LRESULT CALLBACK WindowProc(HWND hwnd, 
						    UINT msg, 
                            WPARAM wparam, 
                            LPARAM lparam)
{
// this is the main message handler of the system
PAINTSTRUCT	ps;		   // used in WM_PAINT
HDC			hdc;	   // handle to a device context

// what is the message 
switch(msg)
	{	
	case WM_CREATE: 
        {
		// do initialization stuff here
		return(0);
		} break;

    case WM_PAINT:
         {
         // start painting
         hdc = BeginPaint(hwnd,&ps);

         // end painting
         EndPaint(hwnd,&ps);
         return(0);
        } break;

	case WM_DESTROY: 
		{
		// kill the application			
		PostQuitMessage(0);
		return(0);
		} break;

	default:break;

    } // end switch

// process any messages that we didn't take care of 
return (DefWindowProc(hwnd, msg, wparam, lparam));

} // end WinProc

// WINMAIN ////////////////////////////////////////////////

int WINAPI WinMain(	HINSTANCE hinstance,
					HINSTANCE hprevinstance,
					LPSTR lpcmdline,
					int ncmdshow)
{
// this is the winmain function

WNDCLASS winclass;	// this will hold the class we create
HWND	 hwnd;		// generic window handle
MSG		 msg;		// generic message
HDC      hdc;       // generic dc
PAINTSTRUCT ps;     // generic paintstruct

// first fill in the window class stucture
winclass.style			= CS_DBLCLKS | CS_OWNDC | 
                          CS_HREDRAW | CS_VREDRAW;
winclass.lpfnWndProc	= WindowProc;
winclass.cbClsExtra		= 0;
winclass.cbWndExtra		= 0;
winclass.hInstance		= hinstance;
winclass.hIcon			= LoadIcon(NULL, IDI_APPLICATION);
winclass.hCursor		= LoadCursor(NULL, IDC_ARROW);
winclass.hbrBackground	= (HBRUSH)GetStockObject(BLACK_BRUSH);
winclass.lpszMenuName	= NULL; 
winclass.lpszClassName	= WINDOW_CLASS_NAME;

// register the window class
if (!RegisterClass(&winclass))
	return(0);

// create the window, note the use of WS_POPUP
if (!(hwnd = CreateWindow(WINDOW_CLASS_NAME, // class
						  "Collision Demo",	 // title
						  WS_POPUP | WS_VISIBLE,
					 	  0,0,	   // x,y
						  WINDOW_WIDTH,  // width
                          WINDOW_HEIGHT, // height
						  NULL,	   // handle to parent 
						  NULL,	   // handle to menu
						  hinstance,// instance
						  NULL)))	// creation parms
return(0);

// save the window handle and instance in a global
main_window_handle = hwnd;
main_instance      = hinstance;

// perform all game console specific initialization
Game_Init();

// enter main event loop
while(1)
	{
	if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))
		{ 
		// test if this is a quit
        if (msg.message == WM_QUIT)
           break;
	
		// translate any accelerator keys
		TranslateMessage(&msg);

		// send the message to the window proc
		DispatchMessage(&msg);
		} // end if
    
    // main game processing goes here
    Game_Main();

	} // end while

// shutdown game and release all resources
Game_Shutdown();

// return to Windows like this
return(msg.wParam);

} // end WinMain

// T3D GAME PROGRAMMING CONSOLE FUNCTIONS ////////////////

int Game_Init(void *parms)
{
// this function is where you do all the initialization 
// for your game

int index; // looping varsIable

char filename[80]; // used to build up filenames

// seed random number generate
srand(Start_Clock());

// start up DirectDraw (replace the parms as you desire)
DDraw_Init(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_BPP);

// load background image
Load_Bitmap_File(&bitmap8bit, "LAVA.BMP");
Create_Bitmap(&background_bmp,0,0,640,480);
Load_Image_Bitmap(&background_bmp, &bitmap8bit,0,0,BITMAP_EXTRACT_MODE_ABS);
Set_Palette(bitmap8bit.palette);
Unload_Bitmap_File(&bitmap8bit);

// load the bitmaps
Load_Bitmap_File(&bitmap8bit, "LAVASHIP.BMP");

// create ship
Create_BOB(&ship,0,0,80,32,2,BOB_ATTR_MULTI_FRAME | BOB_ATTR_VISIBLE, DDSCAPS_SYSTEMMEMORY);

// load the imagery in
for (index=0; index < 2; index++)
    Load_Frame_BOB(&ship, &bitmap8bit, index, index,0,BITMAP_EXTRACT_MODE_CELL);

// unload bitmap image
Unload_Bitmap_File(&bitmap8bit);

// position the ship to left of screen

// use element 0,1 to hold float accurate position
ship.varsF[SHIP_X_POS] = 0;
ship.varsF[SHIP_Y_POS] = screen_height/2;

// use index 2 to hold x velocity
ship.varsF[SHIP_X_VEL] = SHIP_INITIAL_VELOCITY; 

// hide the mouse
ShowCursor(FALSE);

// initialize directinput
DInput_Init();

// acquire the keyboard only
DInput_Init_Keyboard();

// initilize DirectSound
DSound_Init();

// load background sounds
engine_id = DSound_Load_WAV("PULSAR.WAV");

// start the sounds
DSound_Play(engine_id, DSBPLAY_LOOPING);

// set clipping rectangle to screen extents so objects dont
// mess up at edges
RECT screen_rect = {0,0,screen_width,screen_height};
lpddclipper = DDraw_Attach_Clipper(lpddsback,1,&screen_rect);

// return success
return(1);

} // end Game_Init

///////////////////////////////////////////////////////////

int Game_Shutdown(void *parms)
{
// this function is where you shutdown your game and
// release all resources that you allocated

// shut everything down

// kill all the bobs
Destroy_BOB(&ship);

// shutdown directdraw last
DDraw_Shutdown();

// now directsound
DSound_Stop_All_Sounds();
DSound_Shutdown();

// shut down directinput
DInput_Shutdown();

// return success
return(1);

} // end Game_Shutdown

//////////////////////////////////////////////////////////

int Game_Main(void *parms)
{
// this is the workhorse of your game it will be called
// continuously in real-time this is like main() in C
// all the calls for you game go here!

int index; // looping var

static int delay = 30; // initial delay per frame

// start the timing clock
DWORD start_time = Start_Clock();

// lock back buffer and copy background into it
DDraw_Lock_Back_Surface();

// draw background
Draw_Bitmap(&background_bmp, back_buffer, back_lpitch,0);

// unlock back surface
DDraw_Unlock_Back_Surface();

// read keyboard
DInput_Read_Keyboard();

// update delay
if (keyboard_state[DIK_RIGHT]) 
   delay+=5;
else
if (delay > 5 && keyboard_state[DIK_LEFT]) 
   delay-=5;


// draw the ship
ship.x = ship.varsF[SHIP_X_POS]+0.5;
ship.y = ship.varsF[SHIP_Y_POS]+0.5;
ship.curr_frame = 0;
Draw_BOB(&ship, lpddsback);

// draw shadow
ship.curr_frame = 1;
ship.x-=64;
ship.y+=128;
Draw_BOB(&ship, lpddsback);

// draw the title
Draw_Text_GDI("Time Based Kinematic Motion DEMO, Press <ESC> to Exit.",10, 10,RGB(255,255,255), lpddsback);

sprintf(buffer, "Frame rate = %f, use <RIGHT>, <LEFT> arrows to change load", 1000*1/(float)delay );
Draw_Text_GDI(buffer,10, 25,RGB(255,255,255), lpddsback);

sprintf(buffer,"Ship Velocity is %f pixels/sec",1000*ship.varsF[SHIP_X_VEL]);
Draw_Text_GDI(buffer,10, 40,RGB(255,255,255), lpddsback);

// this models the load in the game
Wait_Clock(delay);

// flip the surfaces
DDraw_Flip();

// move the ship based on time //////////////////////////////////
// x = x + v*dt

// compute dt
float dt = Get_Clock() - start_time; // in milliseconds

// move based on 30 pixels per seconds or .03 pixels per millisecond
ship.varsF[SHIP_X_POS]+=(ship.varsF[SHIP_X_VEL]*dt);

// test for off screen
if (ship.varsF[SHIP_X_POS] > screen_width+ship.width)
   ship.varsF[SHIP_X_POS] = -ship.width;

//////////////////////////////////////////////////////

// check of user is trying to exit
if (KEY_DOWN(VK_ESCAPE) || keyboard_state[DIK_ESCAPE])
    {
    PostMessage(main_window_handle, WM_DESTROY,0,0);

    // stop all sounds
    DSound_Stop_All_Sounds();

    // do a screen transition
    Screen_Transitions(SCREEN_DARKNESS,NULL,0);
    } // end if

// return success
return(1);

} // end Game_Main

//////////////////////////////////////////////////////////