一，frambuffer.c
1.头文件及结构体
#include "framebuffer.h"
#include <linux/fb.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <math.h>void *pmem;
struct fb_var_screeninfo vinf;
2.初始化framebuffer
int init_fb(char *devname)
{//1. 打开显示设备int fd = open(devname, O_RDWR); if (-1 == fd){perror("fail open fb");return -1;}//2、获取显示设备相关参数 分辨率 位深度int ret = ioctl(fd, FBIOGET_VSCREENINFO, &vinf);if (-1 ==ret){perror("fail ioctl");return -1;}printf("xres = %d, yres = %d\n", vinf.xres, vinf.yres);printf("xres_virtual = %d, yres_virtual = %d\n", vinf.xres_virtual, vinf.yres_virtual);printf("bits_per_pixel : %d\n", vinf.bits_per_pixel);size_t len = vinf.xres_virtual * vinf.yres_virtual * vinf.bits_per_pixel/8;//3, 建立显存和用户空间的映射关系pmem = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);if ((void *)-1 == pmem){perror("fail mmap");return -1;}return fd;
}
3.画一个点
void draw_point(int x, int y, unsigned int col)
{if (x >= vinf.xres || y >= vinf.yres){return ;}if (vinf.bits_per_pixel == RGB888_FMT){unsigned int *p = pmem;*(p + y * vinf.xres_virtual + x) = col;}else if (vinf.bits_per_pixel == RGB565_FMT){unsigned short *p = pmem; *(p + y * vinf.xres_virtual + x) = col;}return ;
}
4.销毁
void uninit_fb(int fd)
{size_t len = vinf.xres_virtual * vinf.yres_virtual * vinf.bits_per_pixel/8;munmap(pmem, len);close(fd);
}
5.清屏
void draw_clear(unsigned int col)
{for (int j = 0; j < vinf.xres; j++){for (int i = 0; i < vinf.yres; i++){draw_point(i, j, col);}}
}
6.绘制横线，竖线，矩形，斜线，圆
void draw_h_line(int x, int y, int len, unsigned int col)
{for (int i = x; i < x+len; i++){draw_point(i, y, col);}
}
void draw_s_line(int x, int y, int len, unsigned int col)
{for (int i = y; i < y+len; i++){draw_point(x, i, col);}
}void draw_rectangle(int x, int y, int w, int h, unsigned int col)
{draw_h_line(x, y, w, col);draw_s_line(x, y, h, col);draw_s_line(x+w, y, h, col);draw_h_line(x, y+h, w, col);
}void draw_x_line(int x1, int y1, int x2, int y2, unsigned int col)
{int x = 0;int y = 0;if (x1 == x2){if (y2 > y1){draw_s_line(x1, y1, y2-y1, col);}else{draw_s_line(x2, y2, y1-y2, col); }}double k = (double)(y2-y1)/(double)(x2-x1);double b = y1 - k*x1;for (int x = (x1 > x2 ? x2 : x1); x <= (x1 > x2 ? x1 : x2); x++){y = x * k + b;draw_point(x, y, col);}return ;
}void draw_circle(int x0, int y0, int r, unsigned int col)
{int x = 0;int y = 0;for (double si = 0; si <= 360; si+=0.01){x = r * cos(2 * 3.14159/360 *si) + x0;y = r * sin(2 * 3.14159/360 *si) + y0;draw_point(x, y, col);draw_point(x-1, y, col);draw_point(x+1, y, col);draw_point(x, y-1, col);draw_point(x, y+1, col);}}
7.绘制bmp格式图像
void draw_bmp(int x, int y, char *picname, int w, int h)
{int fd = open(picname, O_RDONLY);if (-1 == fd){perror("fail open bmp");return ;}lseek(fd, 54, SEEK_SET);unsigned char r, g, b;unsigned char *buff = malloc(w*h*3);read(fd, buff, w*h*3);unsigned char *p = buff;for (int j = h-1; j >= 0; j--){for (int i = 0; i < w; i++){b = *p; p++;g = *p; p++;r = *p; p++;if (vinf.bits_per_pixel == RGB888_FMT){unsigned int col = (r << 16) | (g << 8) | (b << 0);draw_point(i+x, j+y, col);}else if (vinf.bits_per_pixel == RGB565_FMT){unsigned short col = ((r >> 3) << 11) | ((g >> 2) << 5) | ((b >> 3) << 0);draw_point(i+x, j+y, col);}}}free(buff);close(fd);
}
8.绘制一个字
void draw_word(int x, int y, unsigned char *word, int w, int h, unsigned int col)
{for (int j = 0; j < h; j++){for (int i = 0; i < w; i++){unsigned char tmp = word[i+j*w];for (int k = 0; k < 8; k++){if (tmp & 0x80){draw_point(i*8+k+x, j+y, col);}else{//文字的背景色}tmp = tmp << 1;}}}
}
9.绘制文字库里的单字
int draw_utf8(UTF8_INFO *info, int x, int y, char* zi, unsigned int col, unsigned int col1)
{unsigned long out = 0 ;int ret = enc_utf8_to_unicode_one((unsigned char*)zi,&out);unsigned char* data = get_utf_data(info,out);unsigned char temp = 0 ;unsigned int i,j,k;unsigned int num = 0;for(i=0;i<info->height;i++){for(j=0;j<info->width/8;j++){temp = data[num++];for(k=0;k<8;k++){if(0x80&temp){draw_point( x+k+j*8, y+i, col);}else{// draw_point( x+k+j*8, y+i, col1);}temp= temp<<1;}}}return ret;
}
10.绘制文字库里的字符串
int draw_utf8_str(UTF8_INFO *info, int arg_x, int arg_y, char* zi, unsigned int col, unsigned int col1)
{char* temp = zi;unsigned int x = arg_x ;unsigned int y = arg_y;while(*temp != '\0'){int ret = draw_utf8(info, x, y, temp, col, col1);x += info->width;if(x > vinf.xres){x = 0;y += info->height;if(y > vinf.yres){y = 0;}}temp += ret;}return 0;
}
二， utf.c
#include "utf.h"/****************************************************************************** 函数名：enc_get_utf8_size* 将一个字符的UTF8编码转换成Unicode(UCS-2和UCS-4)编码.** 参数:* pInput 指向输入缓冲区, 以UTF-8编码*** 返回值:* 成功则返回该字符的UTF8编码所占用的字节数; 失败则返回0.* 注意事项：无******************************************************************************/
int enc_get_utf8_size(const unsigned char pInput)
{unsigned char c = pInput;// 0xxxxxxx 返回0// 10xxxxxx 不存在// 110xxxxx 返回2// 1110xxxx 返回3// 11110xxx 返回4// 111110xx 返回5// 1111110x 返回6if(c< 0x80) return 0;if(c>=0x80 && c<0xC0) return -1;if(c>=0xC0 && c<0xE0) return 2;if(c>=0xE0 && c<0xF0) return 3;if(c>=0xF0 && c<0xF8) return 4;if(c>=0xF8 && c<0xFC) return 5;if(c>=0xFC) return 6;return -1;
}/****************************************************************************** 函数名：enc_utf8_to_unicode_one* 将一个字符的UTF8编码转换成Unicode(UCS-2和UCS-4)编码.** 参数:* pInput 指向输入缓冲区, 以UTF-8编码* Unic 指向输出缓冲区, 其保存的数据即是Unicode编码值,* 类型为unsigned long .** 返回值:* 成功则返回该字符的UTF8编码所占用的字节数; 失败则返回0.** 注意事项:* 1. UTF8没有字节序问题, 但是Unicode有字节序要求;* 字节序分为大端(Big Endian)和小端(Little Endian)两种;* 在Intel处理器中采用小端法表示, 在此采用小端法表示. (低地址存低位)****************************************************************************/
int enc_utf8_to_unicode_one(const unsigned char* pInput, unsigned long *Unic)
{assert(pInput != NULL && Unic != NULL);// b1 表示UTF-8编码的pInput中的高字节, b2 表示次高字节, ...char b1, b2, b3, b4, b5, b6;*Unic = 0x0; // 把 *Unic 初始化为全零int utfbytes = enc_get_utf8_size(*pInput);//int utfbytes = 3;unsigned char *pOutput = (unsigned char *) Unic;switch ( utfbytes ){case 0:*pOutput = *pInput;utfbytes += 1;break;case 2:b1 = *pInput;b2 = *(pInput + 1);if ( (b2 & 0xE0) != 0x80 )return 0;*pOutput = (b1 << 6) + (b2 & 0x3F);*(pOutput+1) = (b1 >> 2) & 0x07;break;case 3:b1 = *pInput;b2 = *(pInput + 1);b3 = *(pInput + 2);if ( ((b2 & 0xC0) != 0x80) || ((b3 & 0xC0) != 0x80) )return 0;*pOutput = (b2 << 6) + (b3 & 0x3F);*(pOutput+1) = (b1 << 4) + ((b2 >> 2) & 0x0F);break;case 4:b1 = *pInput;b2 = *(pInput + 1);b3 = *(pInput + 2);b4 = *(pInput + 3);if ( ((b2 & 0xC0) != 0x80) || ((b3 & 0xC0) != 0x80)|| ((b4 & 0xC0) != 0x80) )return 0;*pOutput = (b3 << 6) + (b4 & 0x3F);*(pOutput+1) = (b2 << 4) + ((b3 >> 2) & 0x0F);*(pOutput+2) = ((b1 << 2) & 0x1C) + ((b2 >> 4) & 0x03);break;case 5:b1 = *pInput;b2 = *(pInput + 1);b3 = *(pInput + 2);b4 = *(pInput + 3);b5 = *(pInput + 4);if ( ((b2 & 0xC0) != 0x80) || ((b3 & 0xC0) != 0x80)|| ((b4 & 0xC0) != 0x80) || ((b5 & 0xC0) != 0x80) )return 0;*pOutput = (b4 << 6) + (b5 & 0x3F);*(pOutput+1) = (b3 << 4) + ((b4 >> 2) & 0x0F);*(pOutput+2) = (b2 << 2) + ((b3 >> 4) & 0x03);*(pOutput+3) = (b1 << 6);break;case 6:b1 = *pInput;b2 = *(pInput + 1);b3 = *(pInput + 2);b4 = *(pInput + 3);b5 = *(pInput + 4);b6 = *(pInput + 5);if ( ((b2 & 0xC0) != 0x80) || ((b3 & 0xC0) != 0x80)|| ((b4 & 0xC0) != 0x80) || ((b5 & 0xC0) != 0x80)|| ((b6 & 0xC0) != 0x80) )return 0;*pOutput = (b5 << 6) + (b6 & 0x3F);*(pOutput+1) = (b5 << 4) + ((b6 >> 2) & 0x0F);*(pOutput+2) = (b3 << 2) + ((b4 >> 4) & 0x03);*(pOutput+3) = ((b1 << 6) & 0x40) + (b2 & 0x3F);break;default:return 0;break;}return utfbytes;
}/****************************************************************************** 函数名：enc_unicode_to_utf8_one* 将一个字符的Unicode(UCS-2和UCS-4)编码转换成UTF-8编码.** 参数:* unic 字符的Unicode编码值* pOutput 指向输出的用于存储UTF8编码值的缓冲区的指针* outsize pOutput缓冲的大小** 返回值:* 返回转换后的字符的UTF8编码所占的字节数, 如果出错则返回 0 .** 注意事项:* 1. UTF8没有字节序问题, 但是Unicode有字节序要求;* 字节序分为大端(Big Endian)和小端(Little Endian)两种;* 在Intel处理器中采用小端法表示, 在此采用小端法表示. (低地址存低位)* 2. 请保证 pOutput 缓冲区有最少有 6 字节的空间大小!****************************************************************************/
int enc_unicode_to_utf8_one(unsigned long unic, unsigned char *pOutput,int outSize){assert(pOutput != NULL);assert(outSize >= 6);if ( unic <= 0x0000007F ){// * U-00000000 - U-0000007F: 0xxxxxxx*pOutput = (unic & 0x7F);return 1;}else if ( unic >= 0x00000080 && unic <= 0x000007FF ){// * U-00000080 - U-000007FF: 110xxxxx 10xxxxxx*(pOutput+1) = (unic & 0x3F) | 0x80;*pOutput = ((unic >> 6) & 0x1F) | 0xC0;return 2;}else if ( unic >= 0x00000800 && unic <= 0x0000FFFF ){// * U-00000800 - U-0000FFFF: 1110xxxx 10xxxxxx 10xxxxxx*(pOutput+2) = (unic & 0x3F) | 0x80;*(pOutput+1) = ((unic >> 6) & 0x3F) | 0x80;*pOutput = ((unic >> 12) & 0x0F) | 0xE0;return 3;}else if ( unic >= 0x00010000 && unic <= 0x001FFFFF ){// * U-00010000 - U-001FFFFF: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx*(pOutput+3) = (unic & 0x3F) | 0x80;*(pOutput+2) = ((unic >> 6) & 0x3F) | 0x80;*(pOutput+1) = ((unic >> 12) & 0x3F) | 0x80;*pOutput = ((unic >> 18) & 0x07) | 0xF0;return 4;}else if ( unic >= 0x00200000 && unic <= 0x03FFFFFF ){// * U-00200000 - U-03FFFFFF: 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx*(pOutput+4) = (unic & 0x3F) | 0x80;*(pOutput+3) = ((unic >> 6) & 0x3F) | 0x80;*(pOutput+2) = ((unic >> 12) & 0x3F) | 0x80;*(pOutput+1) = ((unic >> 18) & 0x3F) | 0x80;*pOutput = ((unic >> 24) & 0x03) | 0xF8;return 5;}else if ( unic >= 0x04000000 && unic <= 0x7FFFFFFF ){// * U-04000000 - U-7FFFFFFF: 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx*(pOutput+5) = (unic & 0x3F) | 0x80;*(pOutput+4) = ((unic >> 6) & 0x3F) | 0x80;*(pOutput+3) = ((unic >> 12) & 0x3F) | 0x80;*(pOutput+2) = ((unic >> 18) & 0x3F) | 0x80;*(pOutput+1) = ((unic >> 24) & 0x3F) | 0x80;*pOutput = ((unic >> 30) & 0x01) | 0xFC;return 6;}return 0;
}/****************************************************************************** 函数名：init_utf8* 将字库文件读取到缓存区** 参数:* info 缓存区数据结构** 返回值:* 无** 注意事项：* 无*****************************************************************************/
void init_utf8(UTF8_INFO *info)
{int ret = 0 ;int fd = open(info->path,O_RDONLY);if(-1 == fd){exit(1);}struct stat st;ret = stat(info->path,&st);if(-1 == ret){printf("get zi ku file size error");exit(1);}if(NULL == info->g_ziku_data){info->g_ziku_data= malloc(st.st_size);}ret = read(fd,info->g_ziku_data,st.st_size);if(ret<=0){printf("read utf-8 info error!");exit(1);}
// info->height = heigh;
// info->width = width;info->zimo_size = st.st_size /65536;close(fd);
}/****************************************************************************** 函数名：uninit_utf8* 回收字模缓存区空间** 参数:* info 需要回收的字模缓存区** 返回值:* 无** 注意事项：* 无*****************************************************************************/
void uninit_utf8(UTF8_INFO *info)
{free(info->g_ziku_data);
}/****************************************************************************** 函数名：get_utf_data* 根据编号得到字模** 参数:* info 字模缓存区* out 字的编码** 返回值:* 字模起点位置** 注意事项：* 无*****************************************************************************/
unsigned char* get_utf_data(UTF8_INFO *info,int out)
{unsigned char* temp = info->g_ziku_data+out*info->width*info->height/8;return temp;
}
三，头文件
1.frame buffer.h
#ifndef __FRAMEBUFFER_H__
#define __FRAMEBUFFER_H__#include "utf.h"#define RGB888_FMT 32
#define RGB565_FMT 16extern int init_fb(char *devname);
extern void draw_point(int x,int y, unsigned int col);
extern void uninit_fb(int fd);
extern void draw_clear(unsigned int col);extern void draw_h_line(int x, int y, int len, unsigned int col);
extern void draw_s_line(int x, int y, int len, unsigned int col);
extern void draw_rectangle(int x, int y, int w, int h, unsigned int col);
extern void draw_x_line(int x1, int y1, int x2, int y2, unsigned int col);
extern void draw_circle(int x0, int y0, int r, unsigned int col);
extern void draw_bmp(int x, int y, char *picname, int w, int h);
extern void draw_word(int x, int y, unsigned char *word, int w, int h, unsigned int col);
extern int draw_utf8(UTF8_INFO *info, int x, int y, char* zi, unsigned int col, unsigned int col1);
extern int draw_utf8_str(UTF8_INFO *info, int arg_x, int arg_y, char* zi, unsigned int col, unsigned int col1);#endif
2.utf.h
#ifndef UTF
#define UTF
#ifdef __cplusplus
extern "C"{
#endif
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <stdlib.h>
#include <fcntl.h>
#define u8 unsigned char
#define u16 unsigned short
#define u32 unsigned int#define ZIKUK_FILE_SMALL "./ziku"
#define ZIKUK_FILE_BIG "./ziku2_w32_h32"
/***字模文件缓存**/
typedef struct
{char path[256];//字模库文件路径unsigned width; //字模宽度unsigned height;//字模高度unsigned zimo_size;//每个字字模字节数unsigned char* g_ziku_data;//字模库文件缓存区
}UTF8_INFO;extern void init_utf8(UTF8_INFO *info);
extern unsigned char *get_utf_data(UTF8_INFO *info,int out);extern void uninit_utf8(UTF8_INFO *info);
extern int enc_utf8_to_unicode_one(const unsigned char* pInput, unsigned long *Unic);
extern int enc_unicode_to_utf8_one(unsigned long unic, unsigned char *pOutput,int outSize);
extern int enc_get_utf8_size(const unsigned char pInput);#ifdef __cplusplus
}
#endif
#endif // UTF
四，主函数
#include <stdio.h>
#include "framebuffer.h"unsigned char pu[24*24/8] = {
/*-- 文字: 普 --*/
/*-- 仿宋18; 此字体下对应的点阵为：宽x高=24x24 --*/
0x00,0x00,0x00,0x00,0x03,0x00,0x01,0xC3,0x80,0x00,0xE3,0x00,0x00,0x77,0x00,0x00,
0xFF,0xF0,0x0F,0xFF,0xC0,0x00,0x7E,0xE0,0x06,0x7E,0xE0,0x03,0x7F,0xC0,0x03,0xFF,
0x80,0x01,0x7F,0xFC,0x7F,0xFF,0xE0,0x3E,0x00,0x80,0x03,0xFF,0xC0,0x03,0xFF,0xC0,
0x03,0x81,0xC0,0x03,0xFF,0xC0,0x01,0xFF,0x80,0x01,0x81,0x80,0x01,0xFF,0x80,0x03,
0xFF,0x80,0x01,0x81,0x80,0x00,0x00,0x00
};int main(int argc, const char *argv[])
{//初始化utf8字库UTF8_INFO utf8_info;bzero(&utf8_info, sizeof(UTF8_INFO));strcpy(utf8_info.path, ZIKUK_FILE_BIG);utf8_info.width = 32;utf8_info.height = 32;init_utf8(&utf8_info);int fb_fd = init_fb("/dev/fb0");if (-1 == fb_fd){return -1;}draw_point(400, 300, 0x00ff0000);draw_clear(0x00000000);// draw_rectangle(100,100, 100,200, 0x00ff0000);//draw_x_line(200, 200, 300, 300, 0x0000ffff);//draw_x_line(200, 200, 300, 100, 0x0000ffff);// draw_x_line(300, 300, 100, 100, 0x00ff00ff);draw_circle(200,200, 200, 0x00ffffff);sleep(2);draw_bmp(0, 0, "./res/1.bmp", 800, 600);// draw_word(100, 100, pu, 24/8, 24, 0x00ff0000);draw_utf8_str(&utf8_info, 100, 100, "水产品养殖远程监控系统", 0x00ff0000, 0x00ffffff);uninit_fb(fb_fd);return 0;
}
