G
Guest
I'm trying to learn programming and I've got quite far so far, but I've run
into a few problems, the main ones involving DrawDibDraw. First, 12 bytes
seem to be missing from "bitmapinfoheader" that I see in the hex edittor.
Second, I'm puzzled about the difference with the Dst and Src values and what
they're for. Below my code is where my issues are explained in better detail.
These are my issues:
1. While reading from the BMP file, there seems to be an extra 12 bytes in
the file, as seen in my hex edittor (XVI32). The location of the missing
bytes is commented where it is found. I saved the 24-bit uncompressed BMP
file with "The GIMP".
2. I don't know if I set up the DrawDibDraw function properly, the pointers
and handles especially. I'm still confused about the Dst and Src values.
3. I want the interior part of the window to be 640x480, which excludes
borders, menus, and the title bar. I don't have any menus at the moment
though. I also want the window itself to be centered. The method I have works
fine, but seems awfully complicated so I'm wondering if there's a better way.
4. Without the bitmap reading stuff, my program is using 100% of the CPU
when all other windows programs barely use any of the CPU. Why is this and
how do I fix it? I suspect it has something to do with the while loop in the
WinMain function.
into a few problems, the main ones involving DrawDibDraw. First, 12 bytes
seem to be missing from "bitmapinfoheader" that I see in the hex edittor.
Second, I'm puzzled about the difference with the Dst and Src values and what
they're for. Below my code is where my issues are explained in better detail.
Code:
// First Windows app.cpp : Defines the entry point for the application.
/*
To do before making the first useful Windows application - what background
scaling is (or "The Supernatural Olympics" version 1.1):
Draw images
Syncronize drawing images with monitor refresh rate
Call a function upon pressing a key
*/
/* Trim fat from windows*/
#define WIN32_LEAN_AND_MEAN
#pragma comment(linker, "/subsystem:windows")
/* Pre-processor directives*/
#include "stdafx.h"
#include <stdio.h>
#include <windows.h>
// defines and global vars
#define x 0
#define y 1
short screen_size[2]; // screen resolution (e.g. 1920x1440)
short window_size_base[2]; // expected window size
short window_size[2]; // actual window size
short window_pos[2]; // window position
short title_bar_height; // height of the title bar in pixels
short window_border[2]; // size of the window border
int file_handle; // handle for reading/writing files
char bmp_image[]; // data for the bitmap image
int *img_handle; // pointer for a handle
int *HDC_handle; // pointer for HDC handle
BITMAPINFOHEADER bmp_head;
void draw_test_image()
{
img_handle = DrawDibOpen();
file_handle = fopen("C:\\My Documents\\My programs\\ulillilliacity.bmp",
"rb"); // read the source BMP file to display, binary mode
fseek(file_handle, 2, seek_set); // skip the first two bytes, the file
identifier, the string "BM"
// fill the struct reading from the file
fread(&bmp_head.biSize, 4, 1, file_handle); // actual file size
// 12 bytes missing here, according to what I'm seeing in the hex edittor
fread(&bmp_head.biWidth, 4, 1, file_handle);
fread(&bmp_head.biHeight, 4, 1, file_handle);
fread(&bmp_head.biPlanes, 2, 1, file_handle);
fread(&bmp_head.biBitCount, 2, 1, file_handle);
fread(&bmp_head.biCompression, 4, 1, file_handle);
fread(&bmp_head.biSizeImage, 4, 1, file_handle);
fread(&bmp_head.biXPelsPerMeter, 4, 1, file_handle);
fread(&bmp_head.biYPelsPerMeter, 4, 1, file_handle);
fread(&bmp_head.biClrUsed, 4, 1, file_handle);
fread(&bmp_head.biClrImportant, 4, 1, file_handle);
fread(&bmp_head.biClrImportant, 4, 1, file_handle);
fread(&bmp_image, 1, bmp_head.biSizeImage, file_handle); // read the
remainder of the bits, the image data part
fclose(file_handle);
DrawDibDraw(img_handle, hDC, 64, 48, 512, 384, bmp_head, bmp_image, 64, 48,
512, 384, 0); // still not sure about the first group of numbers
DrawDibClose(img_handle); // free the resources
}
/* Windows Procedure Event Handler*/
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM
lParam)
{
PAINTSTRUCT paintStruct;
/* Device Context*/
HDC hDC; // is this the DC declaration?
/* Text for display*/
char string[] = "Image test - there should be an image below";
/* Switch message, condition that is met will execute*/
switch(message)
{
/* Window is being created*/
case WM_CREATE:
return 0;
break;
/* Window is closing*/
case WM_CLOSE:
PostQuitMessage(0);
return 0;
break;
/* Window needs update*/
case WM_PAINT:
hDC = BeginPaint(hwnd,&paintStruct);
/* Set txt color to blue*/
SetTextColor(hDC, COLORREF(0x00FF8040));
/* Display text in middle of window*/
TextOut(hDC,0,2,string,sizeof(string)-1);
EndPaint(hwnd, &paintStruct);
return 0;
break;
default:
break;
}
return (DefWindowProc(hwnd,message,wParam,lParam));
}
/* Main function*/
int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
WNDCLASSEX windowClass; //window class
HWND hwnd; //window handle
MSG msg; //message
bool done; //flag saying when app is complete
/* Fill out the window class structure*/
windowClass.cbSize = sizeof(WNDCLASSEX);
windowClass.style = CS_HREDRAW | CS_VREDRAW;
windowClass.lpfnWndProc = WndProc;
windowClass.cbClsExtra = 0;
windowClass.cbWndExtra = 0;
windowClass.hInstance = hInstance;
windowClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
windowClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
windowClass.lpszMenuName = NULL;
windowClass.lpszClassName = "MyClass";
windowClass.hIconSm = LoadIcon(NULL, IDI_WINLOGO);
/* Register window class*/
if (!RegisterClassEx(&windowClass))
{
return 0;
}
/* SM_CXBORDER is 1
SM_CYBORDER is 1
SM_CXEDGE is 2
SM_CYEDGE is 2
SM_CXFIXEDFRAME is 3
SM_CYFIXEDFRAME is 3
SM_CXSIZEFRAME is 4
SM_CYSIZEFRAME is 4
SM_CYCAPTION is 18
*/
window_border[x] = GetSystemMetrics(SM_CXSIZEFRAME); // obtain border
sizes, title bar height, and operating resolution
window_border[y] = GetSystemMetrics(SM_CYSIZEFRAME);
title_bar_height = GetSystemMetrics(SM_CYCAPTION); // obtain height of the
title bar
screen_size[x] = GetSystemMetrics(SM_CXSCREEN); // operating resolution
screen_size[y] = GetSystemMetrics(SM_CYSCREEN);
window_size_base[x] = 640; // interior window size
window_size_base[y] = 480;
window_size[x] = window_size_base[x]+window_border[x]*2; // full window
size, including borders and title bar
window_size[y] = window_size_base[y]+window_border[y]*2+title_bar_height;
window_pos[x] = (screen_size[x]/2)-(window_size[x]/2); // center the window
window_pos[y] = (screen_size[y]/2)-(window_size[y]/2);
/* Class registerd, so now create window*/
hwnd = CreateWindowEx(NULL, //extended style
"MyClass", //class name
"First Windows app", //app name
WS_OVERLAPPEDWINDOW | //window style
WS_VISIBLE |
WS_SYSMENU,
window_pos[x],window_pos[y], //x/y coords
window_size[x],window_size[y], //width,height
NULL, //handle to parent
NULL, //handle to menu
hInstance, //application instance
NULL); //no extra parameter's
/* Check if window creation failed*/
if (!hwnd)
return 0;
done = false; //initialize loop condition variable
/* main message loop*/
draw_test_image();
while(!done)
{
PeekMessage(&msg,hwnd,NULL,NULL,PM_REMOVE);
if (msg.message == WM_QUIT) //check for a quit message
{
free(*img_handle);
done = true; //if found, quit app
}
else
{
/* Translate and dispatch to event queue*/
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
return msg.wParam;
}These are my issues:
1. While reading from the BMP file, there seems to be an extra 12 bytes in
the file, as seen in my hex edittor (XVI32). The location of the missing
bytes is commented where it is found. I saved the 24-bit uncompressed BMP
file with "The GIMP".
2. I don't know if I set up the DrawDibDraw function properly, the pointers
and handles especially. I'm still confused about the Dst and Src values.
3. I want the interior part of the window to be 640x480, which excludes
borders, menus, and the title bar. I don't have any menus at the moment
though. I also want the window itself to be centered. The method I have works
fine, but seems awfully complicated so I'm wondering if there's a better way.
4. Without the bitmap reading stuff, my program is using 100% of the CPU
when all other windows programs barely use any of the CPU. Why is this and
how do I fix it? I suspect it has something to do with the while loop in the
WinMain function.