FreeType的简单使用

#include <windows.h> #include <stdio.h> #include <gl\gl.h> #include <gl\glu.h> #define GLUT_DISABLE_ATEXIT_HACK #include "glut.h" #include <ft2build.h> #include FT_FREETYPE_H #include <freetype/freetype.h> #include <freetype/ftglyph.h> #include <math.h> #pragma comment(lib , "freetype2412_D.lib") #pragma comment(lib , "glut32.lib") #pragma comment(lib , "glut.lib") #define MAX_NO_TEXTURES 1 #define CUBE_TEXTURE 0 GLuint texture_id[MAX_NO_TEXTURES]; struct xCharTexture { GLuint m_texID; wchar_t m_chaID; int m_Width; int m_Height; int m_adv_x; int m_adv_y; int m_delta_x; int m_delta_y; public: xCharTexture() { m_texID = 0; m_chaID = 0; m_Width = 0; m_Height = 0; } }g_TexID[65536]; class xFreeTypeLib { FT_Library m_FT2Lib; FT_Face m_FT_Face; int m_w; int m_h; public: xFreeTypeLib() { if (FT_Init_FreeType( &m_FT2Lib) ) exit(0); } void load(const char* font_file , int _w , int _h) { //sqrt(100.0); //加载一个字体,取默认的Face,一般为Regualer if (FT_New_Face( m_FT2Lib, font_file, 0, &m_FT_Face )) { getchar(); exit(0); } FT_Select_Charmap(m_FT_Face, FT_ENCODING_UNICODE); m_w = _w ; m_h = _h; m_FT_Face->num_fixed_sizes; //大小要乘64.这是规定。照做就可以了。 //FT_Set_Char_Size( m_FT_Face , 0 , m_w << 6, 96, 96); FT_Set_Pixel_Sizes(m_FT_Face,m_w, m_h); } GLuint loadChar(wchar_t ch) { if(g_TexID[ch].m_texID) return g_TexID[ch].m_texID; if(FT_Load_Char(m_FT_Face, ch,FT_LOAD_RENDER|FT_LOAD_FORCE_AUTOHINT| (true ? FT_LOAD_TARGET_NORMAL : FT_LOAD_MONOCHROME | FT_LOAD_TARGET_MONO) ) ) { return 0; } xCharTexture& charTex = g_TexID[ch]; //得到字模 FT_Glyph glyph; if(FT_Get_Glyph( m_FT_Face->glyph, &glyph )) return 0; //转化成位图 FT_Render_Glyph( m_FT_Face->glyph, FT_RENDER_MODE_LCD );//FT_RENDER_MODE_NORMAL ); FT_Glyph_To_Bitmap( &glyph, ft_render_mode_normal, 0, 1 ); FT_BitmapGlyph bitmap_glyph = (FT_BitmapGlyph)glyph; //取道位图数据 FT_Bitmap& bitmap=bitmap_glyph->bitmap; //把位图数据拷贝自己定义的数据区里.这样旧可以画到需要的东西上面了。 int width = bitmap.width; int height = bitmap.rows; m_FT_Face->size->metrics.y_ppem; m_FT_Face->glyph->metrics.horiAdvance; charTex.m_Width = width; charTex.m_Height = height; charTex.m_adv_x = m_FT_Face->glyph->advance.x / 64.0f; charTex.m_adv_y = m_FT_Face->size->metrics.y_ppem; //m_FT_Face->glyph->metrics.horiBearingY / 64.0f; charTex.m_delta_x = (float)bitmap_glyph->left; charTex.m_delta_y = (float)bitmap_glyph->top - height; glGenTextures(1,&charTex.m_texID); glBindTexture(GL_TEXTURE_2D,charTex.m_texID); char* pBuf = new char[width * height * 4]; for(int j=0; j < height ; j++) { for(int i=0; i < width; i++) { unsigned char _vl = (i>=bitmap.width || j>=bitmap.rows) ? 0 : bitmap.buffer[i + bitmap.width*j]; pBuf[(4*i + (height - j - 1) * width * 4) ] = 0xff; pBuf[(4*i + (height - j - 1) * width * 4)+1] = 0xff; pBuf[(4*i + (height - j - 1) * width * 4)+2] = 0xff; pBuf[(4*i + (height - j - 1) * width * 4)+3] = _vl; } } glTexImage2D( GL_TEXTURE_2D,0,GL_RGBA,width, height,0,GL_RGBA,GL_UNSIGNED_BYTE,pBuf); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP); glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST ); glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST ); glTexEnvi(GL_TEXTURE_2D,GL_TEXTURE_ENV_MODE,GL_REPLACE); delete[]pBuf; return charTex.m_chaID; } }g_FreeTypeLib; float ratio; xCharTexture* getTextChar(wchar_t ch) { g_FreeTypeLib.loadChar(ch); return &g_TexID[ch]; } wchar_t g_UnicodeString[]=L"FFFFFFFFFFFFFFFFFFFFFFFFFFFFF文字测试, aabicABCDESEDFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" ; void drawText(wchar_t* _strText,int x , int y, int maxW , int h) { int sx = x; int sy = y; int maxH = h; for(int i = 0 ; i < wcslen(_strText) ; i ++) { if(_strText[i] =='\n') { sx = x ; sy += maxH + 12; continue; } xCharTexture* pCharTex = getTextChar(_strText[i]); glBindTexture(GL_TEXTURE_2D,pCharTex->m_texID); glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST ); glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST ); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA); //glDisable(GL_TEXTURE_2D); int w = pCharTex->m_Width; int h = pCharTex->m_Height; int ch_x = sx + pCharTex->m_delta_x; int ch_y = sy - h - pCharTex->m_delta_y; if(maxH < h) maxH = h; glBegin ( GL_QUADS ); { glTexCoord2f(0.0f, 1.0f); glVertex3f(ch_x , ch_y , 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(ch_x + w, ch_y , 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(ch_x + w, ch_y + h, 1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(ch_x , ch_y + h, 1.0f); } glEnd(); sx += pCharTex->m_adv_x; if(sx > x + maxW) { sx = x ; sy += maxH + 12; } } } void init(void) { glShadeModel(GL_SMOOTH); // Enable Smooth Shading glClearColor(0.0f, 0.0f, 0.0f, 0.5f); // Black Background glEnable ( GL_COLOR_MATERIAL ); glColorMaterial ( GL_FRONT, GL_AMBIENT_AND_DIFFUSE ); // g_FreeTypeLib.load("E:\\3d\\25D\\freetype\\freetypetest\\Debug\\msyh.ttf",20,20); g_FreeTypeLib.load("simkai.ttf",30,30); glDisable ( GL_CULL_FACE ); //glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); } void reshape( int w, int h ) { // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if(h == 0) h = 1; ratio = 1.0f * w / h; // Reset the coordinate system before modifying glMatrixMode(GL_PROJECTION); glLoadIdentity(); // Set the viewport to be the entire window glViewport(0, 0, w, h); glOrtho(0,w,h,0,-100,200); // Set the clipping volume glMatrixMode(GL_MODELVIEW); glLoadIdentity(); gluLookAt(0, 0, 30 ,0 , 0 ,10 , 0.0f , 1.0f , 0.0f); } void display( void ) { glClearColor(0.0f , 0.0f , 0.6f , 1.0f); glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); //glLoadIdentity ( ); //glPushMatrix(); //glTranslatef ( 0.0, 0.0, -5.0 ); glEnable ( GL_TEXTURE_2D ); drawText(g_UnicodeString,50,50,900,25); //glPopMatrix(); glutSwapBuffers(); } void keyboard ( unsigned char key, int x, int y ) // Create Keyboard Function { switch ( key ) { case 27: // When Escape Is Pressed... exit ( 0 ); // Exit The Program break; // Ready For Next Case default: // Now Wrap It Up break; } } void arrow_keys ( int a_keys, int x, int y ) // Create Special Function (required for arrow keys) { switch ( a_keys ) { case GLUT_KEY_UP: // When Up Arrow Is Pressed... glutFullScreen ( ); // Go Into Full Screen Mode break; case GLUT_KEY_DOWN: // When Down Arrow Is Pressed... glutReshapeWindow ( 500, 500 ); // Go Into A 500 By 500 Window break; default: break; } } int main ( int argc, char** argv ) // Create Main Function For Bringing It All Together { glutInit ( &argc, argv ); // Erm Just Write It =) glutInitDisplayMode ( GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA ); // Display Mode glutInitWindowPosition (0,0); glutInitWindowSize ( 500, 500 ); // If glutFullScreen wasn't called this is the window size glutCreateWindow ( "NeHe Lesson 6- Ported by Rustad" ); // Window Title (argv[0] for current directory as title) // glPolygonMode(GL_FRONT_AND_BACK ,GL_LINE ); init (); //glutFullScreen ( ); // Put Into Full Screen glutDisplayFunc ( display ); // Matching Earlier Functions To Th