例子
#include#include #include #include #include FT_FREETYPE_H#define WIDTH 80#define HEIGHT 80/* origin is the upper left corner */unsigned char image[HEIGHT][WIDTH];/* Replace this function with something useful. */voiddraw_bitmap( FT_Bitmap* bitmap, FT_Int x, FT_Int y){ FT_Int i, j, p, q; FT_Int x_max = x + bitmap->width; FT_Int y_max = y + bitmap->rows; for ( i = x, p = 0; i < x_max; i++, p++ ) { for ( j = y, q = 0; j < y_max; j++, q++ ) { if ( i < 0 || j < 0 || i >= WIDTH || j >= HEIGHT ) continue; image[j][i] |= bitmap->buffer[q * bitmap->width + p]; } }}voidshow_image( void ){ int i, j; for ( i = 0; i < HEIGHT; i++ ) { for ( j = 0; j < WIDTH; j++ ) putchar( image[i][j] == 0 ? ' ' : image[i][j] < 128 ? '+' : '*' ); putchar( '\n' ); }}intmain( int argc, char** argv ){ FT_Library library; FT_Face face; FT_GlyphSlot slot; FT_Matrix matrix; /* transformation matrix */ FT_Vector pen; /* untransformed origin */ FT_Error error; char* filename; char* text; double angle; int target_height; int n, num_chars; if ( argc != 3 ) { fprintf ( stderr, "usage: %s font sample-text\n", argv[0] ); exit( 1 ); } filename = argv[1]; /* first argument */ text = argv[2]; /* second argument */ num_chars = strlen( text ); angle = ( 0.0 / 360 ) * 3.14159 * 2; /* use 25 degrees */ target_height = HEIGHT; error = FT_Init_FreeType( &library ); /* initialize library */ /* error handling omitted */ error = FT_New_Face( library, argv[1], 0, &face ); /* create face object */ /* error handling omitted */#if 0 /* use 50pt at 100dpi */ error = FT_Set_Char_Size( face, 50 * 64, 0, 100, 0 ); /* set character size */ /* pixels = 50 /72 * 100 = 69 个像素点*/#else FT_Set_Pixel_Sizes(face, 24, 0);#endif /* error handling omitted */ slot = face->glyph; /* set up matrix */ matrix.xx = (FT_Fixed)( cos( angle ) * 0x10000L ); matrix.xy = (FT_Fixed)(-sin( angle ) * 0x10000L ); matrix.yx = (FT_Fixed)( sin( angle ) * 0x10000L ); matrix.yy = (FT_Fixed)( cos( angle ) * 0x10000L ); /* the pen position in 26.6 cartesian space coordinates; */ /* start at (0,40) relative to the upper left corner */ pen.x = 0 * 64; pen.y = ( target_height - 40 ) * 64; for ( n = 0; n < num_chars; n++ ) { /* set transformation */ FT_Set_Transform( face, &matrix, &pen ); /* load glyph image into the slot (erase previous one) */ error = FT_Load_Char( face, text[n], FT_LOAD_RENDER ); if ( error ) continue; /* ignore errors */ /* now, draw to our target surface (convert position) */ draw_bitmap( &slot->bitmap, slot->bitmap_left, target_height - slot->bitmap_top ); /* increment pen position */ pen.x += slot->advance.x; pen.y += slot->advance.y; } show_image(); FT_Done_Face ( face ); FT_Done_FreeType( library ); return 0;}
1.编译free_type
配置 ./configure
编译 make
安装 sudo make install
gcc -o example1 example1.c
error: freetype/config/ftheader.h: No such file or directory
example1.c:12:10: error: #include expects "FILENAME" or <FILENAME>指定头文件目录编译
gcc -o example1 example1.c -I /usr/local/include/freetype2
报错缺库
example1.c:(.text+0x1ea): undefined reference to `FT_Init_FreeType'
example1.c:(.text+0x216): undefined reference to `FT_New_Face'example1.c:(.text+0x236): undefined reference to `FT_Set_Pixel_Sizes'example1.c:(.text+0x24d): undefined reference to `cos'example1.c:(.text+0x285): undefined reference to `sin'example1.c:(.text+0x2bd): undefined reference to `sin'example1.c:(.text+0x2f5): undefined reference to `cos'example1.c:(.text+0x360): undefined reference to `FT_Set_Transform'example1.c:(.text+0x386): undefined reference to `FT_Load_Char'example1.c:(.text+0x409): undefined reference to `FT_Done_Face'example1.c:(.text+0x415): undefined reference to `FT_Done_FreeType'
example1.c:(.text+0x24d): undefined reference to `cos'
example1.c:(.text+0x285): undefined reference to `sin'example1.c:(.text+0x2bd): undefined reference to `sin'example1.c:(.text+0x2f5): undefined reference to `cos'指定库编译freetype gcc -o example1 example1.c -I /usr/local/include/freetype2 –lfreetype
缺数学类定义
example1.c:(.text+0x24d): undefined reference to `cos'
example1.c:(.text+0x285): undefined reference to `sin'example1.c:(.text+0x2bd): undefined reference to `sin'example1.c:(.text+0x2f5): undefined reference to `cos'
加-lm为加数学类库意思 gcc -o example1 example1.c -I /usr/local/include/freetype2 -lfreetype -lm
执行exampe1 用宋体文件 显示abcfg
./example1 ./simsun.ttc abcfg
陈志朋uicode码为 48 96 D7 5F 67 0B
int chinese_str[] = {0x9648,0x5fd7,0x670b};
for ( n = 0; n < 4; n++ ) { /* set transformation */ FT_Set_Transform( face, &matrix, &pen ); /* load glyph image into the slot (erase previous one) */ error = FT_Load_Char( face, chinese_str[n], FT_LOAD_RENDER ); if ( error ) continue; /* ignore errors */ /* now, draw to our target surface (convert position) */ draw_bitmap( &slot->bitmap, slot->bitmap_left, target_height - slot->bitmap_top ); /* increment pen position */ pen.x += slot->advance.x; pen.y += slot->advance.y; }
./example1 ./simsun.ttc abc
无法直接使用“abc陈志朋a”
使用宽字符
添加头文件include<wchar.h>
#include <wchar.h>
wchar_t * chinese_str = L"陈志朋~陈";
unsigned int *p = (wchar_t *)chinese_str;int i = 0;
printf("uicode: \n");
for( i = 0; i < wcslen(chinese_str); i++) { printf("0x%x " , p[i]); }printf("\n");
return 0;85:27: error: converting to execution character set: Invalid or incomplete multibyte or wide character
代码格式为asii应转化为uicode码
gcc -finput-charset=GBK -fexec-charset=UTF-8 -o example1 example1.c -I /usr/local/include/freetype2 -lfreetype -lm
结果
uicode:
0x9648 0x5fd7 0x670b 0x7e 0x9648
打印出位置大小参数
添加头文件#include FT_GLYPH_H
FT_BBox bbox; FT_Glyph glyph; // 将FT_GlyphSlot glyph转化为 FT_Glyph glyph; error = FT_Get_Glyph( face->glyph, &glyph ); if(error) { printf("FT_Get_Glyph error \n"); } /*从glyph中获取bbox*/ FT_Glyph_Get_CBox( glyph, FT_GLYPH_BBOX_TRUNCATE, &bbox ); //汉字uicode码 printf("uicode: %x\n", chinese_str[n]); //汉字位置原点 printf("origin.x /64 = %d , origin.y /64 = %d ", pen.x/64, pen.y/64); //最小最大X,Y printf("x_min = %d ,x_max = %d, y_min = %d, y_max = %d \n", bbox.xMin, bbox.xMax, bbox.yMin, bbox.yMax); //X,Y偏移值 printf("slot.advance.x/64 = %d, slot.advance.y/64 = %d \n", slot->advance.x/64, slot->advance.y/64);
结果
uicode: 9648
origin.x /64 = 0 , origin.y /64 = 40 x_min = 2 ,x_max = 23, y_min = 37, y_max = 60 slot.advance.x/64 = 24, slot.advance.y/64 = 0 uicode: 5fd7origin.x /64 = 24 , origin.y /64 = 40 x_min = 25 ,x_max = 47, y_min = 38, y_max = 60 slot.advance.x/64 = 24, slot.advance.y/64 = 0 uicode: 670borigin.x /64 = 48 , origin.y /64 = 40 x_min = 48 ,x_max = 70, y_min = 37, y_max = 59 slot.advance.x/64 = 24, slot.advance.y/64 = 0 uicode: 7eorigin.x /64 = 72 , origin.y /64 = 40 x_min = 73 ,x_max = 84, y_min = 55, y_max = 60 slot.advance.x/64 = 12, slot.advance.y/64 = 0 uicode: 9648origin.x /64 = 84 , origin.y /64 = 40 x_min = 86 ,x_max = 107, y_min = 37, y_max = 60 slot.advance.x/64 = 24, slot.advance.y/64 = 0