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Krajczyk

freetype2 opengl access violation error...need help

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I've been trying to get truetype fonts to show up in my opengl project using the freetype2 lib. The project compiles ok but I keep getting an access violation error on the line with FT_GlyphSlot slot = face->glyph; in the function drawText; When i turn off the parts resposible for fonts all renders ok so I'm only posting the truetype stuff. Am I messing up something with the order of defining FT_Face face that its causing the violation? ////////////////////////// ////// includes #include <windows.h> #include <gl/gl3.h> #include <gl/glu.h> #include <stdio.h> #include <iostream> #include <vector> #include <fstream> #include <string> #include <soil/SOIL.h> #include <math.h> #include "render.h" #include "component.h" #include "inputs.h" #include <ft2build.h> #include <ft2build.h> #include FT_FREETYPE_H /////////////////////////////// // defined before main loop // FT_Library library; FT_Face face; GLuint texture; int nextpoweroftwo(int x) { double logbase2 = log(float(x)) / log(float(2)); //return round(pow(2,ceil(logbase2))); return (int)((pow(2,ceil(logbase2)))+0.5); } void drawFillRectTextured (float x, float y, float width, float height) { glBegin (GL_QUADS); glTexCoord2f (0.0f,0.0f); glVertex2f (x,y); glTexCoord2f (1.0f, 0.0f); glVertex2f (x+width, y); glTexCoord2f (1.0f, 1.0f); glVertex2f (x+width, y+height); glTexCoord2f (0.0f, 1.0f); glVertex2f (x, y+height); glEnd (); } void drawBitmap (FT_Bitmap * bitmap, FT_Int left, FT_Int top) { int width = nextpoweroftwo( bitmap->width ); int height = nextpoweroftwo( bitmap->rows ); GLubyte* buffer = new GLubyte[ 2 * width * height]; for(int j=0; j <height;j++) { for(int i=0; i < width; i++){ buffer[2*(i+j*width)]= buffer[2*(i+j*width)+1] = (i>=bitmap->width || j>=bitmap->rows) ? 0 : bitmap->buffer[i + bitmap->width*j]; } } glBindTexture( GL_TEXTURE_2D, texture ); glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR ); glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR ); glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, buffer ); delete [] buffer; //setColor(GREEN); glEnable (GL_TEXTURE_2D); drawFillRectTextured(left, top, bitmap->width, bitmap->rows); glDisable (GL_TEXTURE_2D); } void drawText (string text, FT_Face face, int pen_x, int pen_y) { int error; FT_GlyphSlot slot = face->glyph; for (unsigned int n=0;n<text.length();n++) { error = FT_Load_Char( face, 't', FT_LOAD_RENDER ); if ( error ) continue; drawBitmap (&slot->bitmap, slot->bitmap_left + pen_x, slot->bitmap_top + pen_y); pen_x += slot->advance.x >> 6; pen_y += slot->advance.y >> 6; } } void loadFTFonts () { int error; error = FT_New_Face ( library, "./arial.ttf", 0, &face ); if (error == FT_Err_Unknown_File_Format) { // cerr << "Font isn't in the correct format." << endl; //exit (1); } else if (error) { //cerr << "Error opening font." << endl; //exit (1); } error = FT_Set_Pixel_Sizes( face, /* handle to face object */ 0, /* pixel_width */ 18 ); if (error) { // cerr << "FT_Set_Pixel_Sizes failed to set the pixel sizes!" << endl; // exit (1); } } //////////////////////////////////////// // inside my initiliazation function void init() { loadFTFonts (); .... setting up threads & opengl window } ///////////////////////////////////////// /// main engine drawing loop void mainloop(){ drawText ("test the text", face, 10, 20); draw(); }; /////////////////////////////////////////////////////////////// //// setting up winmain and initializing init() the main loop #ifdef _DEBUG int WINAPI WinMain(HINSTANCE i, HINSTANCE p, LPSTR cmd, int n) #else int WinMainCRTStartup() #endif { PIXELFORMATDESCRIPTOR pfd; HWND hwnd; HDC hdc; int pixelFormat; #ifdef FULLSCREEN DEVMODE dmScreenSettings; // Device Mode #endif #ifndef _DEBUG HINSTANCE i = GetModuleHandle(NULL); #endif /* init the pixelformat descriptor */ RtlZeroMemory(&pfd,sizeof(PIXELFORMATDESCRIPTOR)); // Clear the struct pfd.nSize=sizeof(PIXELFORMATDESCRIPTOR); // Size pfd.nVersion=1; // Version pfd.dwFlags=PFD_DRAW_TO_WINDOW|PFD_SUPPORT_OPENGL|PFD_DOUBLEBUFFER; // Selected flags pfd.iPixelType=PFD_TYPE_RGBA; // Pixelformat pfd.cColorBits=32; // Pixel depth pfd.cDepthBits=16; // Zbuffer depth pfd.iLayerType=PFD_MAIN_PLANE; // Place the pixelformat on the main plane #ifdef FULLSCREEN /* init the resolution change settings */ RtlZeroMemory(&dmScreenSettings,sizeof(dmScreenSettings)); // Clear the struct dmScreenSettings.dmSize=sizeof(dmScreenSettings); // Size Of The Devmode Structure dmScreenSettings.dmPelsWidth = 640; // Selected Screen Width dmScreenSettings.dmPelsHeight = 480; // Selected Screen Height dmScreenSettings.dmBitsPerPel = 32; // Selected Bits Per Pixel dmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT; // Notify which fields we have used if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL) return 0; #endif /* setup the window handle */ hwnd=CreateWindowEx(WS_EX_TOOLWINDOW, L"STATIC", L"blipblop", WS_POPUP|WS_CLIPSIBLINGS | WS_CLIPCHILDREN | WS_VISIBLE|WS_CLIPSIBLINGS|WS_CLIPCHILDREN, 0, 0, 800, 600, 0, 0, i, 0); /* select the pixel format for the current window */ hdc = GetDC(hwnd); pixelFormat = ChoosePixelFormat(hdc, &pfd); SetPixelFormat(hdc, pixelFormat, &pfd); wglMakeCurrent(hdc, wglCreateContext(hdc)); /* cursor be gone */ SetCursor(0); init(); /* loop until escape is pressed all normal windows messages are ignored */ while (!GetAsyncKeyState(VK_ESCAPE)) { mainloop(); // nifty effects here SwapBuffers(hdc); // display the cool stuff } return 0; // exit to OS } // clean up I've been stuck trying to get my head around implementing freetype for the past 2 days. The include paths and libs for freetype are setup so they don't give off any errors.

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