获得位图之freetype

freetype只获得位图步骤有：1.初始化freetype库，2..打开字体文件3.设置点阵大小（用默认的也行）4.用FT_Load_Char来获得字体的点阵，就像gbk或点阵用索引来的得到位图一样。不过freetype的坐标挺复杂下面上传一张图来对应程序理解就容易了。

#include <config.h>#include <fonts_manager.h>#include <ft2build.h>#include FT_FREETYPE_H#include FT_GLYPH_Hstatic int FreeTypeFontInit(char *pcFontFile, unsigned int dwFontSize);static int FreeTypeGetFontBitmap(unsigned int dwCode, PT_FontBitMap ptFontBitMap);static T_FontOpr g_tFreeTypeFontOpr = {.name          = "freetype",.FontInit      = FreeTypeFontInit,.GetFontBitmap = FreeTypeGetFontBitmap,};static FT_Library g_tLibrary;static FT_Face g_tFace;static FT_GlyphSlot g_tSlot;static int FreeTypeFontInit(char *pcFontFile, unsigned int dwFontSize){int iError;/* 显示矢量字体 */iError = FT_Init_FreeType(&g_tLibrary );   /* initialize library *//* error handling omitted */if (iError){DBG_PRINTF("FT_Init_FreeType failed\n");return -1;}iError = FT_New_Face(g_tLibrary, pcFontFile, 0, &g_tFace); /* 打开字体文件create face object *//* error handling omitted */if (iError){DBG_PRINTF("FT_Init_FreeType failed\n");return -1;}g_tSlot = g_tFace->glyph;//把字体轮廓保存 ，以后要用轮廓取位图 iError = FT_Set_Pixel_Sizes(g_tFace, dwFontSize, 0);//设置像素大小 if (iError){DBG_PRINTF("FT_Set_Pixel_Sizes failed : %d\n", dwFontSize);return -1;}return 0;}static int FreeTypeGetFontBitmap(unsigned int dwCode, PT_FontBitMap ptFontBitMap){int iError;int iPenX = ptFontBitMap->iCurOriginX;int iPenY = ptFontBitMap->iCurOriginY;#if 0FT_Vector tPen;tPen.x = 0;tPen.y = 0;/* set transformation */FT_Set_Transform(g_tFace, 0, &tPen);#endif/* load glyph image into the slot (erase previous one) *///iError = FT_Load_Char(g_tFace, dwCode, FT_LOAD_RENDER );iError = FT_Load_Char(g_tFace, dwCode, FT_LOAD_RENDER | FT_LOAD_MONOCHROME);//得字体点阵 if (iError){DBG_PRINTF("FT_Load_Char error for code : 0x%x\n", dwCode);return -1;}//坐标转化 笛卡尔坐标（原点在左下）转换为lcd坐标 （原点左上） //DBG_PRINTF("iPenX = %d, iPenY = %d, bitmap_left = %d, bitmap_top = %d, width = %d, rows = %d\n", iPenX, iPenY, g_tSlot->bitmap_left, g_tSlot->bitmap_top, g_tSlot->bitmap.width, g_tSlot->bitmap.rows);ptFontBitMap->iXLeft    = iPenX + g_tSlot->bitmap_left;ptFontBitMap->iYTop     = iPenY - g_tSlot->bitmap_top;ptFontBitMap->iXMax     = ptFontBitMap->iXLeft + g_tSlot->bitmap.width;ptFontBitMap->iYMax     = ptFontBitMap->iYTop  + g_tSlot->bitmap.rows;ptFontBitMap->iBpp      = 1;ptFontBitMap->iPitch    = g_tSlot->bitmap.pitch;ptFontBitMap->pucBuffer = g_tSlot->bitmap.buffer;ptFontBitMap->iNextOriginX = iPenX + g_tSlot->advance.x / 64;ptFontBitMap->iNextOriginY = iPenY;//DBG_PRINTF("iXLeft = %d, iYTop = %d, iXMax = %d, iYMax = %d, iNextOriginX = %d, iNextOriginY = %d\n", ptFontBitMap->iXLeft, ptFontBitMap->iYTop, ptFontBitMap->iXMax, ptFontBitMap->iYMax, ptFontBitMap->iNextOriginX, ptFontBitMap->iNextOriginY);return 0;}int FreeTypeInit(void){return RegisterFontOpr(&g_tFreeTypeFontOpr);}