BSArch/04/bmp_fractal.c

/* Betriebssystem & Middleware
 *
 * Betriebssystemarchitektur SS 2006
 *
 * Uebung 4.4 
 */

// $Id: bmp_fractal.c,v 1.3 2006/07/01 11:45:35 joko Exp $

#include <windows.h>
#include <stdio.h>
#include <errno.h>

#define XSIZE 500
#define YSIZE 500
#include "algorithm.h"


/* BMP Header */
unsigned char header[54]={0x42,0x4d,              // signature BM
                            0xe6,0x71,0x0b,0x0,   // filesize 750054
                            0x0,0x0,0x0,0x0,      // reserved 
                            0x36,0x0,0x0,0x0,     // image offset 54
                            0x28,0x0,0x0,0x0,     // size of header follows 40
                            0xf4,0x1,0x0,0x0,     // with of image 500
                            0xf4,0x1,0x0,0x0,     // height of image 500
                            0x1,0x0,              // number of planes  1
                            0x18,0x0,             // number of pixel 24
                            0x0,0x0,0x0,0x0,      // compression  
                            0xb0,0x71,0x0b,0x0,   // size of image 750000
                            0x0,0x0,0x0,0x0,      // xres
                            0x0,0x0,0x0,0x0,      // yres   
                            0x0,0x0,0x0,0x0,      // number of colortables    
                            0x0,0x0,0x0,0x0       // number of important colors
                        };


void printErrorAndExit(const char *msg, DWORD err) {
        LPSTR lpMsgBuf;
        if(FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|
                                  FORMAT_MESSAGE_FROM_SYSTEM | 
                                          FORMAT_MESSAGE_IGNORE_INSERTS,
                                                NULL,
                                                err,
                                          MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
                                          (LPTSTR) &lpMsgBuf,
                                          0,
                                          NULL ))
        {
                fprintf(stderr,"%s : %s\n",msg,lpMsgBuf);
                LocalFree(lpMsgBuf);
        }
        else
        {
                fprintf(stderr,"Error at FormatMesage: %d\n",err=GetLastError());
        }
        exit(err);
}


void write_blank_file(char *filename) {

  FILE *fd;
  int len, i, img_size;

  // open file handle
  fd = fopen(filename, "wb+");
  if (NULL == fd) {
    perror("open");
    exit(1);
  }

  // write bmp header to file
  len = fwrite(header, 1, sizeof(header), fd);
  
  // error checking
  if (-1 == len || len != sizeof(header)) {
    perror("write");
    exit(2);
  }
  
  // write three null-bytes for each pixel to file to create a black picture
  img_size = XSIZE * YSIZE;
  for (i = 0; i < img_size; i++) {
    len = fwrite("\0\0\0", 1, 3, fd);
    if (-1 == len || len != 3) {
      perror("write");
      exit(4);
    }
  }
  
  // close file handle
  fclose(fd);
}


int main(int argc, char *argv[]) {

  // MMF support
  DWORD err;
  HANDLE hMap, hFile;
  LPVOID pData;
  unsigned char *pDataBitmap, *pDataBitmapCurrent;

  // fractal calculation
  int x, y;
  char bgr[3];
  
  
  // create empty bmp-file (black background)
  write_blank_file("test.bmp");

  /* open file for reading and writing */
  hFile = CreateFile("test.bmp", GENERIC_WRITE|GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
  if (INVALID_HANDLE_VALUE == hFile) {
    err = GetLastError();
    printErrorAndExit("Error at CreateFile",err);
  }

  /* create the file mapping object */
  hMap = CreateFileMapping(hFile, NULL, PAGE_READWRITE, 0, 0, NULL);
  if (NULL == hMap) {
    printErrorAndExit("Error at CreateFileMapping", GetLastError());
  }
  
  /* map the whole file into the process context */
  pData = MapViewOfFile(hMap, FILE_MAP_WRITE, 0, 0, 0);
  if (NULL == pData) {
    printErrorAndExit("Error at MapViewOfFile", GetLastError());
  }

  
  // calculate pointer to beginning of bitmap
  pDataBitmap = (unsigned char *)((INT_PTR)pData + sizeof(header));
  
  // debugging
  printf("pos. of file: %p\n", pData);
  printf("pos. of bitmap: %p\n", pDataBitmap);

  // pointer to current pixel
  pDataBitmapCurrent = pDataBitmap;

  /*
  // turn bitmap into white wand
  for (offset = 0; offset < 500 * 500 * 3; offset++) {
    //pDataBitmap[offset] = 255;
    *pDataBitmapCurrent = 255;
    pDataBitmapCurrent++;
  }
  */

  // calculate fractal
  for (y=YSIZE-1; y>=0; y--) {
          for (x=0; x<XSIZE; x++) {
            getColorValuesAt(x * (2.0 / XSIZE) - 1.5, y * (2.0 / YSIZE) - 1.0, &bgr[2], &bgr[1], &bgr[0]); 
            
            // debugging
            //printf("pointer: %p\n", pDataBitmapCurrent);
            
            // transfer color values to current pixel
            pDataBitmapCurrent[0] = bgr[0];
            pDataBitmapCurrent[1] = bgr[1];
            pDataBitmapCurrent[2] = bgr[2];
            
            // move pointer to next pixel
            pDataBitmapCurrent += 3;
            
          }
          //no padding required because 1500%4 =0
  }

  
  /* write the result into the file */
  if (!FlushViewOfFile(pData, 0)) {
    err = GetLastError();
    printErrorAndExit("Error at UnmapViewOfFile", err);
  }

  /* remove the mapped file */
  if (!UnmapViewOfFile(pData)) {
    err = GetLastError();
    printErrorAndExit("Error at UnmapViewOfFile", err);
    exit(err);
  }
  
  /* cleanup handles */
  if (!CloseHandle(hMap) || !CloseHandle(hFile) ) {
    err = GetLastError();
    printErrorAndExit("Error at CloseHandle", err);
  }

}
1	joko	1.1	/* Betriebssystem & Middleware
2			*
3			* Betriebssystemarchitektur SS 2006
4			*
5			* Uebung 4.4
6			*/
7	joko	1.3
8	joko	1.4	// $Id: bmp_fractal.c,v 1.3 2006/07/01 11:45:35 joko Exp $
9	joko	1.3
10			#include <windows.h>
11	joko	1.1	#include <stdio.h>
12			#include <errno.h>
13
14			#define XSIZE 500
15			#define YSIZE 500
16			#include "algorithm.h"
17
18	joko	1.3
19	joko	1.2	/* BMP Header */
20	joko	1.1	unsigned char header[54]={0x42,0x4d, // signature BM
21			0xe6,0x71,0x0b,0x0, // filesize 750054
22			0x0,0x0,0x0,0x0, // reserved
23			0x36,0x0,0x0,0x0, // image offset 54
24			0x28,0x0,0x0,0x0, // size of header follows 40
25			0xf4,0x1,0x0,0x0, // with of image 500
26			0xf4,0x1,0x0,0x0, // height of image 500
27			0x1,0x0, // number of planes 1
28			0x18,0x0, // number of pixel 24
29			0x0,0x0,0x0,0x0, // compression
30			0xb0,0x71,0x0b,0x0, // size of image 750000
31			0x0,0x0,0x0,0x0, // xres
32			0x0,0x0,0x0,0x0, // yres
33			0x0,0x0,0x0,0x0, // number of colortables
34			0x0,0x0,0x0,0x0 // number of important colors
35			};
36
37	joko	1.3
38			void printErrorAndExit(const char *msg, DWORD err) {
39			LPSTR lpMsgBuf;
40			if(FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER\|
41			FORMAT_MESSAGE_FROM_SYSTEM \|
42			FORMAT_MESSAGE_IGNORE_INSERTS,
43			NULL,
44			err,
45			MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
46			(LPTSTR) &lpMsgBuf,
47			0,
48			NULL ))
49			{
50			fprintf(stderr,"%s : %s\n",msg,lpMsgBuf);
51			LocalFree(lpMsgBuf);
52			}
53			else
54			{
55			fprintf(stderr,"Error at FormatMesage: %d\n",err=GetLastError());
56			}
57			exit(err);
58			}
59
60
61			void write_blank_file(char *filename) {
62
63			FILE *fd;
64			int len, i, img_size;
65
66			// open file handle
67			fd = fopen(filename, "wb+");
68			if (NULL == fd) {
69			perror("open");
70			exit(1);
71			}
72
73			// write bmp header to file
74			len = fwrite(header, 1, sizeof(header), fd);
75
76			// error checking
77			if (-1 == len \|\| len != sizeof(header)) {
78			perror("write");
79			exit(2);
80			}
81
82			// write three null-bytes for each pixel to file to create a black picture
83			img_size = XSIZE * YSIZE;
84			for (i = 0; i < img_size; i++) {
85			len = fwrite("\0\0\0", 1, 3, fd);
86			if (-1 == len \|\| len != 3) {
87			perror("write");
88			exit(4);
89	joko	1.1	}
90	joko	1.3	}
91
92			// close file handle
93			fclose(fd);
94			}
95
96
97			int main(int argc, char *argv[]) {
98
99	joko	1.4	// MMF support
100			DWORD err;
101	joko	1.3	HANDLE hMap, hFile;
102			LPVOID pData;
103			unsigned char pDataBitmap, pDataBitmapCurrent;
104	joko	1.4
105			// fractal calculation
106			int x, y;
107			char bgr[3];
108	joko	1.3
109
110	joko	1.4	// create empty bmp-file (black background)
111	joko	1.3	write_blank_file("test.bmp");
112
113			/* open file for reading and writing */
114			hFile = CreateFile("test.bmp", GENERIC_WRITE\|GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
115			if (INVALID_HANDLE_VALUE == hFile) {
116			err = GetLastError();
117			printErrorAndExit("Error at CreateFile",err);
118			}
119
120			/* create the file mapping object */
121			hMap = CreateFileMapping(hFile, NULL, PAGE_READWRITE, 0, 0, NULL);
122			if (NULL == hMap) {
123			printErrorAndExit("Error at CreateFileMapping", GetLastError());
124			}
125
126			/* map the whole file into the process context */
127			pData = MapViewOfFile(hMap, FILE_MAP_WRITE, 0, 0, 0);
128			if (NULL == pData) {
129			printErrorAndExit("Error at MapViewOfFile", GetLastError());
130			}
131
132
133			// calculate pointer to beginning of bitmap
134			pDataBitmap = (unsigned char *)((INT_PTR)pData + sizeof(header));
135
136			// debugging
137			printf("pos. of file: %p\n", pData);
138			printf("pos. of bitmap: %p\n", pDataBitmap);
139
140			// pointer to current pixel
141			pDataBitmapCurrent = pDataBitmap;
142
143			/*
144			// turn bitmap into white wand
145			for (offset = 0; offset < 500 * 500 * 3; offset++) {
146			//pDataBitmap[offset] = 255;
147			*pDataBitmapCurrent = 255;
148			pDataBitmapCurrent++;
149			}
150			*/
151
152			// calculate fractal
153			for (y=YSIZE-1; y>=0; y--) {
154			for (x=0; x<XSIZE; x++) {
155			getColorValuesAt(x * (2.0 / XSIZE) - 1.5, y * (2.0 / YSIZE) - 1.0, &bgr[2], &bgr[1], &bgr[0]);
156
157			// debugging
158			//printf("pointer: %p\n", pDataBitmapCurrent);
159
160			// transfer color values to current pixel
161			pDataBitmapCurrent[0] = bgr[0];
162			pDataBitmapCurrent[1] = bgr[1];
163			pDataBitmapCurrent[2] = bgr[2];
164
165			// move pointer to next pixel
166			pDataBitmapCurrent += 3;
167
168			}
169			//no padding required because 1500%4 =0
170			}
171
172
173			/* write the result into the file */
174			if (!FlushViewOfFile(pData, 0)) {
175			err = GetLastError();
176			printErrorAndExit("Error at UnmapViewOfFile", err);
177			}
178
179			/* remove the mapped file */
180			if (!UnmapViewOfFile(pData)) {
181			err = GetLastError();
182			printErrorAndExit("Error at UnmapViewOfFile", err);
183			exit(err);
184			}
185
186			/* cleanup handles */
187			if (!CloseHandle(hMap) \|\| !CloseHandle(hFile) ) {
188			err = GetLastError();
189			printErrorAndExit("Error at CloseHandle", err);
190			}
191	joko	1.1
192			}
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