// DEMO7_9.CPP 8-bit clipping demo
// INCLUDES ///////////////////////////////////////////////
#define WIN32_LEAN_AND_MEAN // just say no to MFC
#define INITGUID
#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> // include directdraw
// DEFINES ////////////////////////////////////////////////
// defines for windows
#define WINDOW_CLASS_NAME "WINCLASS1"
// default screen size
#define SCREEN_WIDTH 640 // size of screen
#define SCREEN_HEIGHT 480
#define SCREEN_BPP 8 // bits per pixel
#define MAX_COLORS_PALETTE 256 // maximum colors in 256 color palette
// TYPES //////////////////////////////////////////////////////
// basic unsigned types
typedef unsigned short USHORT;
typedef unsigned short WORD;
typedef unsigned char UCHAR;
typedef unsigned char BYTE;
// MACROS //////////////////////////////////////////////////////
#define KEYDOWN(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)
#define KEYUP(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 0 : 1)
// this builds a 16 bit color value in 5.5.5 format (1-bit alpha mode)
#define _RGB16BIT555(r,g,b) ((b & 31) + ((g & 31) << 5) + ((r & 31) << 10))
// this builds a 16 bit color value in 5.6.5 format (green dominate mode)
#define _RGB16BIT565(r,g,b) ((b & 31) + ((g & 63) << 5) + ((r & 31) << 11))
// this builds a 32 bit color value in A.8.8.8 format (8-bit alpha mode)
#define _RGB32BIT(a,r,g,b) ((b) + ((g) << 8) + ((r) << 16) + ((a) << 24))
// initializes a direct draw struct
#define DDRAW_INIT_STRUCT(ddstruct) { memset(&ddstruct,0,sizeof(ddstruct)); ddstruct.dwSize=sizeof(ddstruct); }
// PROTOTYPES /////////////////////////////////////////////////
LPDIRECTDRAWCLIPPER DDraw_Attach_Clipper(LPDIRECTDRAWSURFACE7 lpdds,
int num_rects,
LPRECT clip_list);
// GLOBALS ////////////////////////////////////////////////////
HWND main_window_handle = NULL; // globally track main window
int window_closed = 0; // tracks if window is closed
HINSTANCE hinstance_app = NULL; // globally track hinstance
// directdraw stuff
LPDIRECTDRAW7 lpdd = NULL; // dd4 object
LPDIRECTDRAWSURFACE7 lpddsprimary = NULL; // dd primary surface
LPDIRECTDRAWSURFACE7 lpddsback = NULL; // dd back surface
LPDIRECTDRAWPALETTE lpddpal = NULL; // a pointer to the created dd palette
LPDIRECTDRAWCLIPPER lpddclipper = NULL; // dd clipper
PALETTEENTRY palette[256]; // color palette
PALETTEENTRY save_palette[256]; // used to save palettes
DDSURFACEDESC2 ddsd; // a direct draw surface description struct
DDBLTFX ddbltfx; // used to fill
DDSCAPS2 ddscaps; // a direct draw surface capabilities struct
HRESULT ddrval; // result back from dd calls
DWORD start_clock_count = 0; // used for timing
char buffer[80]; // general printing buffer
// 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
char buffer[80]; // used to print strings
// what is the message
switch(msg)
{
case WM_CREATE:
{
// do initialization stuff here
// return success
return(0);
} break;
case WM_PAINT:
{
// simply validate the window
hdc = BeginPaint(hwnd,&ps);
// end painting
EndPaint(hwnd,&ps);
// return success
return(0);
} break;
case WM_DESTROY:
{
// kill the application, this sends a WM_QUIT message
PostQuitMessage(0);
// return success
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
///////////////////////////////////////////////////////////
int Game_Main(void *parms = NULL, int num_parms = 0)
{
// this is the main loop of the game, do all your processing
// here
RECT source_rect, // used to hold the destination RECT
dest_rect; // used to hold the destination RECT
// make sure this isn't executed again
if (window_closed)
return(0);
// for now test if user is hitting ESC and send WM_CLOSE
if (KEYDOWN(VK_ESCAPE))
{
PostMessage(main_window_handle,WM_CLOSE,0,0);
window_closed = 1;
} // end if
// get a random rectangle for source
int x1 = rand()%SCREEN_WIDTH;
int y1 = rand()%SCREEN_HEIGHT;
int x2 = rand()%SCREEN_WIDTH;
int y2 = rand()%SCREEN_HEIGHT;
// get a random rectangle for destination
int x3 = rand()%SCREEN_WIDTH;
int y3 = rand()%SCREEN_HEIGHT;
int x4 = rand()%SCREEN_WIDTH;
int y4 = rand()%SCREEN_HEIGHT;
// now set up the RECT structure to fill the region from
// (x1,y1) to (x2,y2) on the source surface
source_rect.left = x1;
source_rect.top = y1;
source_rect.right = x2;
source_rect.bottom = y2;
// now set up the RECT structure to fill the region from
// (x3,y3) to (x4,y4) on the destination surface
dest_rect.left = x3;
dest_rect.top = y3;
dest_rect.right = x4;
dest_rect.bottom = y4;
// make the blitter call
if (FAILED(lpddsprimary->Blt(&dest_rect, // pointer to dest RECT
lpddsback, // pointer to source surface
&source_rect,// pointer to source RECT
DDBLT_WAIT, // control flags
NULL))) // pointer to DDBLTFX holding info
return(0);
// return success or failure or your own return code here
return(1);
} // end Game_Main
////////////////////////////////////////////////////////////
int Game_Init(void *parms = NULL, int num_parms = 0)
{
// this is called once after the initial window is created and
// before the main event loop is entered, do all your initialization
// here
// create IDirectDraw interface 7.0 object and test for error
if (FAILED(DirectDrawCreateEx(NULL, (void **)&lpdd, IID_IDirectDraw7, NULL)))
return(0);
// set cooperation to full screen
if (FAILED(lpdd->SetCooperativeLevel(main_window_handle,
DDSCL_FULLSCREEN | DDSCL_ALLOWMODEX |
DDSCL_EXCLUSIVE | DDSCL_ALLOWREBOOT)))
return(0);
// set display mode
if (FAILED(lpdd->SetDisplayMode(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_BPP,0,0)))
return(0);
// clear ddsd and set size
DDRAW_INIT_STRUCT(ddsd);
// enable valid fields
ddsd.dwFlags = DDSD_CAPS | DDSD_BACKBUFFERCOUNT;
// set the backbuffer count field to 1, use 2 for triple buffering
ddsd.dwBackBufferCount = 1;
// request a complex, flippable
ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE | DDSCAPS_COMPLEX | DDSCAPS_FLIP;
// create the primary surface
if (FAILED(lpdd->CreateSurface(&ddsd, &lpddsprimary, NULL)))
return(0);
// now query for attached surface from the primary surface
// this line is needed by the call
ddsd.ddsCaps.dwCaps = DDSCAPS_BACKBUFFER;
// get the attached back buffer surface
if (FAILED(lpddsprimary->GetAttachedSurface(&ddsd.ddsCaps, &lpddsback)))
return(0);
// clear all entries defensive programming
memset(palette,0,MAX_COLORS_PALETTE*sizeof(PALETTEENTRY));
// create a R,G,B,GR gradient palette
for (int index=0; index < MAX_COLORS_PALETTE; index++)
{
// set each entry
if (index < 64) // shades of red
palette[index].peRed = index*4;
else // shades of green
if (index >= 64 && index < 128)
palette[index].peGreen = (index-64)*4;
else // shades of blue
if (index >= 128 && index < 192)
palette[index].peBlue = (index-128)*4;
else // shades of grey
if (index >= 192 && index < 256)
palette[index].peRed = palette[index].peGreen =
palette[index].peBlue = (index-192)*4;
// set flag to force directdraw to leave alone
palette[index].peFlags = PC_NOCOLLAPSE;
} // end for index
// draw a color gradient in back buffer
DDRAW_INIT_STRUCT(ddsd);
// lock the back buffer
if (FAILED(lpddsback->Lock(NULL,&ddsd, DDLOCK_SURFACEMEMORYPTR | DDLOCK_WAIT,NULL)))
return(0);
// get alias to start of surface memory for fast addressing
UCHAR *video_buffer = (UCHAR *)ddsd.lpSurface;
// draw the gradient
for (int index_y=0; index_y < SCREEN_HEIGHT; index_y++)
{
// fill next line with color
memset((void *)video_buffer,index_y % 256,SCREEN_WIDTH);
// advance pointer
video_buffer+=ddsd.lPitch;
} // end for index_y
// unlock the back buffer
if (FAILED(lpddsback->Unlock(NULL)))
return(0);
// now create and attach clipper
RECT rect_list[3] = {{10,10,50,50},
{100,100,200,200},
{300,300, 500, 450}};
if (FAILED(lpddclipper = DDraw_Attach_Clipper(lpddsprimary,3,rect_list)))
return(0);
// return success or failure or your own return code here
return(1);
} // end Game_Init
/////////////////////////////////////////////////////////////
int Game_Shutdown(void *parms = NULL, int num_parms = 0)
{
// this is called after the game is exited and the main event
// loop while is exited, do all you cleanup and shutdown here
// first the palette
if (lpddpal)
{
lpddpal->Release();
lpddpal = NULL;
} // end if
// now the back buffer surface
if (lpddsback)
{
lpddsback->Release();
lpddsback = NULL;
} // end if
// now the primary surface
if (lpddsprimary)
{
lpddsprimary->Release();
lpddsprimary = NULL;
} // end if
// now blow away the IDirectDraw4 interface
if (lpdd)
{
lpdd->Release();
lpdd = NULL;
} // end if
// return success or failure or your own return code here
return(1);
} // end Game_Shutdown
///////////////////////////////////////////////////////////
LPDIRECTDRAWCLIPPER DDraw_Attach_Clipper(LPDIRECTDRAWSURFACE7 lpdds,
int num_rects,
LPRECT clip_list)
{
// this function creates a clipper from the sent clip list and attaches
// it to the sent surface
int index; // looping var
LPDIRECTDRAWCLIPPER lpddclipper; // pointer to the newly created dd clipper
LPRGNDATA region_data; // pointer to the region data that contains
// the header and clip list
// first create the direct draw clipper
if (FAILED(lpdd->CreateClipper(0,&lpddclipper,NULL)))
return(NULL);
// now create the clip list from the sent data
// first allocate memory for region data
region_data = (LPRGNDATA)malloc(sizeof(RGNDATAHEADER)+num_rects*sizeof(RECT));
// now copy the rects into region data
memcpy(region_data->Buffer, clip_list, sizeof(RECT)*num_rects);
// set up fields of header
region_data->rdh.dwSize = sizeof(RGNDATAHEADER);
region_data->rdh.iType = RDH_RECTANGLES;
region_data->rdh.nCount = num_rects;
region_data->rdh.nRgnSize = num_rects*sizeof(RECT);
region_data->rdh.rcBound.left = 64000;
region_data->rdh.rcBound.top = 64000;
region_data->rdh.rcBound.right = -64000;
region_data->rdh.rcBound.bottom = -64000;
// find bounds of all clipping regions
for (index=0; index<num_rects; index++)
{
// test if the next rectangle unioned with the current bound is larger
if (clip_list[index].left < region_data->rdh.rcBound.left)
region_data->rdh.rcBound.left = clip_list[index].left;
if (clip_list[index].right > region_data->rdh.rcBound.right)
region_data->rdh.rcBound.right = clip_list[index].right;
if (clip_list[index].top < region_data->rdh.rcBound.top)
region_data->rdh.rcBound.top = clip_list[index].top;
if (clip_list[index].bottom > region_data->rdh.rcBound.bottom)
region_data->rdh.rcBound.bottom = clip_list[index].bottom;
} // end for index
// now we have computed the bounding rectangle region and set up the data
// now let's set the clipping list
if (FAILED(lpddclipper->SetClipList(region_data, 0)))
{
// release memory and return error
free(region_data);
return(NULL);
} // end if
// now attach the clipper to the surface
if (FAILED(lpdds->SetClipper(lpddclipper)))
{
// release memory and return error
free(region_data);
return(NULL);
} // end if
// all is well, so release memory and send back the pointer to the new clipper
free(region_data);
return(lpddclipper);
} // end DDraw_Attach_Clipper
// WINMAIN ////////////////////////////////////////////////
int WINAPI WinMain( HINSTANCE hinstance,
HINSTANCE hprevinstance,
LPSTR lpcmdline,
int ncmdshow)
{
WNDCLASSEX winclass; // this will hold the class we create
HWND hwnd; // generic window handle
MSG msg; // generic message
HDC hdc; // graphics device context
// first fill in the window class stucture
winclass.cbSize = sizeof(WNDCLASSEX);
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;
winclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
// save hinstance in global
hinstance_app = hinstance;
// register the window class
if (!RegisterClassEx(&winclass))
return(0);
// create the window
if (!(hwnd = CreateWindowEx(NULL, // extended style
WINDOW_CLASS_NAME, // class
"DirectDraw Clipping Demo", // title
WS_POPUP | WS_VISIBLE,
0,0, // initial x,y
SCREEN_WIDTH,SCREEN_HEIGHT, // initial width, height
NULL, // handle to parent
NULL, // handle to menu
hinstance,// instance of this application
NULL))) // extra creation parms
return(0);
// save main window handle
main_window_handle = hwnd;
// initialize game here
Game_Init();
// enter main event loop
while(TRUE)
{
// test if there is a message in queue, if so get it
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
// closedown game here
Game_Shutdown();
// return to Windows like this
return(msg.wParam);
} // end WinMain
///////////////////////////////////////////////////////////
void Blit_clipped(int x, int y, // position to draw bitmap
int width, int height, // size of bitmap in pixels
UCHAR *bitmap, // pointer to bitmap data
UCHAR *video_buffer) // pointer to video buffer surface
{
// this function blits and clips the image sent in bitmap to the
// destination surface pointed to by video_buffer
// the function assumes a 640x480x8 mode with linear pitch
// first do trivial rejections of bitmap, is it totally invisible?
if ((x >= SCREEN_WIDTH) || (y>= SCREEN_HEIGHT) ||
((x + width) <= 0) || ((y + height) <= 0))
return;
// clip source rectangle
// pre-compute the bounding rect to make life easy
int x1 = x;
int y1 = y;
int x2 = x1 + width - 1;
int y2 = y1 + height -1;
// upper left hand corner first
if (x1 < 0)
x1 = 0;
if (y1 < 0)
y1 = 0;
// now lower left hand corner
if (x2 >= SCREEN_WIDTH)
x2 = SCREEN_WIDTH-1;
if (y2 >= SCREEN_HEIGHT)
y2 = SCREEN_HEIGHT-1;
// now we know to draw only the portions of the bitmap from (x1,y1) to (x2,y2)
// compute offsets into bitmap on x,y axes, we need this to compute starting point
// to rasterize from
int x_off = x1 - x;
int y_off = y1 - y;
// compute number of columns and rows to blit
int dx = x2 - x1 + 1;
int dy = y2 - y1 + 1;
// compute starting address in video_buffer
video_buffer += (x1 + y1*640);
// compute starting address in bitmap to scan data from
bitmap += (x_off + y_off*width);
// at this point bitmap is pointing to the first pixel in the bitmap that needs to
// be blitted, and video_buffer is pointing to the memory location on the destination
// buffer to put it, so now enter rasterizer loop
UCHAR pixel; // used to read/write pixels
for (int index_y = 0; index_y < dy; index_y++)
{
// inner loop, where the action takes place
for (int index_x = 0; index_x < dx; index_x++)
{
// read pixel from source bitmap, test for transparency and plot
if ((pixel = bitmap[index_x]))
video_buffer[index_x] = pixel;
} // end for index_x
// advance pointers
video_buffer+=640; // bytes per scanline
bitmap +=width; // bytes per bitmap row
} // end for index_y
} // end Blit_Clipped