用freetype转换字符串成位图数据问题？
这是我的转化代码，转换出来的效果图：
我是转换一个字符串：HELLO，但是为什么最后成了两个，而且宽和高似乎都给成了两倍，以下是代码，请大神分析下下面的代码有问题吗？如何修改
static int GetBitmap( char* szFontFile, wchar_t* swText, int ulLen, int nFontSize, int nSpace, BITMAP_S *stBitmap)
{
FT_Library ftLib = NULL;
FT_Face ftFace = NULL;
FT_Error ftError = 0;
FT_Bitmap ftBitmap;
FT_BitmapGlyph ftBmpGlyph;
FT_Glyph ftGlyph;
FT_GlyphSlot ftGlyphslot;
int i, j, k, temp;
int start_x = 0, start_y = 0;
int nChHeight = 0, nChWidth = 0, nTextWidth = 0;
size_t size = 0;
unsigned char** pTextAlpha = NULL;
int BgHeight = nFontSize + 5; /* 背景图形的高度，这个高度要大于字体的高度，所以是+5 */
ftError = FT_Init_FreeType(&ftLib);
if (ftError)
{
printf("FT_Init_FreeType() Failed!\n");
ftLib = 0;
return -1;
}
printf("========fontfile=%s\n", szFontFile);
ftError = FT_New_Face(ftLib, szFontFile, 0, &ftFace);
/*if (ftError == FT_Err_Unknown_File_Format)
{
printf("FT_New_Face() Failed! FT_Err_Unknown_File_Format\n");
return -2;
}
else */if (ftError)
{
printf("FT_New_Face() Failed %d! Other Error!\n", ftError);
return -3;
}
pTextAlpha = (uint8_t**)malloc(sizeof(uint8_t*)*BgHeight); //分配内存，用于存储字体背景的数据
if (NULL == pTextAlpha)
{
printf("malloc() Failed!\n");
return -1;
}
for (i=0; i < BgHeight; i++)
{
pTextAlpha[i] = (uint8_t*)malloc(sizeof(uint8_t)*1); //为背景图的每一行分配内存
if (NULL == pTextAlpha[i])
{
printf("malloc() Failed! %d\n", i);
return -1;
}
}
ftError = FT_Select_Charmap(ftFace, FT_ENCODING_UNICODE); //设置字体的编码方式
if (ftError)
{
printf("FT_Select_Charmap() Failed! error=%d\n", ftError);
return ftError;
}
ftError = FT_Set_Pixel_Sizes(ftFace, 0, nFontSize); //设置字体大小
if (ftError)
{
printf("FT_Set_Pixel_Sizes() Failed! error=%d\n",ftError);
return ftError;
}
uint8_t *data;
ftGlyphslot = ftFace->glyph;
printf("======================ulen = %d\n", ulLen);
for (temp = 0; temp < ulLen; temp++)
{
printf("#######################swText[%d]=%04x\n", temp,swText[temp]);
ftError = FT_Load_Char(ftFace, swText[temp], FT_LOAD_RENDER | FT_LOAD_NO_AUTOHINT);//提取一个字形图像
if (ftError)
{
printf("FT_Load_Char() Failed!, ftError=%d\n", ftError);
continue;
}
ftError = FT_Get_Glyph(ftFace->glyph, &ftGlyph);
if (ftError)
{
printf("FT_Get_Glyph() Failed!");
return ftError;
}
if (swText[temp] == L' ')//如果取得的为空格
{
printf("M MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM M\n");
k = 0;
nChWidth = (nFontSize - 2) / 2;
nChHeight = nFontSize;
nTextWidth = start_x + nChWidth;
start_y = 0;
for (i = 0; i < BgHeight; i++)
{
pTextAlpha[i] = (uint8_t*)realloc(pTextAlpha[i], sizeof(uint8_t)*nTextWidth);
memset(pTextAlpha[i], 0 ,sizeof(uint8_t)*nTextWidth);
for (j = start_x - nSpace; j < nTextWidth; j++)
{
pTextAlpha[i][j] = 0;
}
}
for (i = 0; i < nChHeight; i++)
{
for (j=0; j< nChWidth; j++)
{
pTextAlpha[start_y+i][start_x+j] = 0;
k++;
}
}
start_x += (nChWidth + nSpace); /* 画笔向右边移动 */
}
else
{
/* 256级灰度字形转换成位图 */
ftError = FT_Glyph_To_Bitmap(&ftGlyph, FT_RENDER_MODE_NORMAL , NULL, 1);
if (ftError)
{
printf("FT_Glyph_To_Bitmap() Failed!\n");
}
ftBmpGlyph = (FT_BitmapGlyph)ftGlyph;
ftBitmap = ftBmpGlyph->bitmap;
k = 0;
printf("XXXXXXXXXX:nFontSize = %d, bitmap_top = %d\n", nFontSize, ftGlyphslot->bitmap_top);
printf("XXXXXXXXXX:ftBitmap.rows = %d, BgHeight = %d\n", ftBitmap.rows, BgHeight);
start_y = nFontSize - ftGlyphslot->bitmap_top + 2; /* 获取起点的y轴坐标 */
//start_y = nFontSize - ftBitmap.rows + 2;
if(start_y < 0)
{
start_y = 0;
}
if (ftBitmap.rows > BgHeight)
{
nChHeight = nFontSize;
}
else
{
nChHeight = ftBitmap.rows;
}
if (nChHeight + start_y > BgHeight)
{
nChHeight = BgHeight - start_y;
}
nChWidth = ftBitmap.width;
nTextWidth = start_x + ftBitmap.width;
printf("XXXXXXXXXX:nChHeight = %d, nChWidth = %d, nTextWidth = %d\n",nChHeight, nChWidth, nTextWidth);
for (i=0; i<BgHeight; i++)
{
pTextAlpha[i] = (uint8_t*)realloc(pTextAlpha[i], nTextWidth);
for (j = start_x - nSpace; j < nTextWidth; j++)
{
if(j < 0) j = 0;
pTextAlpha[i][j] = 0;
}
}
for (i = 0; i < BgHeight; i++)
{
for (j = 0; j < nChWidth; j++)
{
if (i >= start_y && i < start_y + nChHeight)
{
pTextAlpha[i][start_x + j] = ftBitmap.buffer[k];
k++;
}
else
{
pTextAlpha[i][start_x + j] = 0;
}
}
}
start_x += (nChWidth + nSpace);
FT_Done_Glyph(ftGlyph);
printf("FT_Done_Glyph() Success!\n");
ftGlyph = NULL;
}
}
FT_Done_Face(ftFace);
ftFace = NULL;
FT_Done_FreeType(ftLib);
ftLib = NULL;
stBitmap->u32Width = nTextWidth;
stBitmap->u32Height = BgHeight;
size = sizeof(uint8_t) * nTextWidth * BgHeight;
stBitmap->pData = (uint8_t*)malloc(size);
memset(stBitmap->pData, 0, size);
printf("===================nTextWidth = %d\n", nTextWidth);
printf("===================BgHeight = %d\n", BgHeight);
printf("===================nChHeight = %d\n", nChHeight);
k = 0;
for (i = 0; i < BgHeight; i++)
{
memcpy(((char*)stBitmap->pData) + k, pTextAlpha[i], nTextWidth);
k += nTextWidth;
free(pTextAlpha[i]);
pTextAlpha[i] = NULL;
}
free(pTextAlpha);
pTextAlpha = NULL;
return 0;
}
无非两个原因：（1）字符串本身有2遍hello重复（2）你画了2次
for (temp = 0; temp < ulLen; temp++) 这里下断点看 ulLen 的值是多少。