Reputation: 25
I have written an application that uses FreeType to render text onto a window. I have built the debug and release version which both run fine from visual studio 2015. I have set my runtime library for linking to /MDd. I also included the font OCRAEXT.TTF in resource files.
Here is the code the uses FreeType:
TextRenderer::TextRenderer(GLuint width, GLuint height)
{
//Load and configure shader
this->TextShader = ResourceManager::LoadShader("VertexText.vert", "FragmentText.frag", nullptr, "text");
this->TextShader.SetMatrix4("projection", glm::ortho(0.0f, static_cast<GLfloat>(width), static_cast<GLfloat>(height), 0.0f), GL_TRUE);
this->TextShader.SetInteger("text", 0);
//configure VAO/VBO for texture quads
glGenVertexArrays(1, &this->VAO);
glGenBuffers(1, &this->VBO);
glBindVertexArray(this->VAO);
glBindBuffer(GL_ARRAY_BUFFER, this->VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(GLfloat) * 6 * 4, NULL, GL_DYNAMIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), 0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
}
void TextRenderer::Load(std::string font, GLuint fontSize)
{
//first clear the previously loaded characters
this->Characters.clear();
//then initialise and load the Freetype library
FT_Library ft;
if (FT_Init_FreeType(&ft)) //All functions return a value different than 0 whenever an error occurred
std::cout << "ERROR::FREETYPE: Could not init freetype library" << std::endl;
//Load font as face
FT_Face face;
if (FT_New_Face(ft, font.c_str(), 0, &face))
std::cout << "ERROR::FREETYPE: Failed to load font" << std::endl;
//set size to load glyphs as
FT_Set_Pixel_Sizes(face, 0, fontSize);
//disable byte-alignment restriction
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
//then for the first 128 ASCII characters, pre-load/compile their characters and store them
for (GLubyte c = 0; c < 128; c++)
{
//Load character glyph
if (FT_Load_Char(face, c, FT_LOAD_RENDER))
{
std::cout << "ERROR::FREETYPE: Failed to load glyph" << std::endl;
continue;
}
//generate texture
GLuint texture;
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexImage2D(
GL_TEXTURE_2D,
0,
GL_RED,
face->glyph->bitmap.width,
face->glyph->bitmap.rows,
0,
GL_RED,
GL_UNSIGNED_BYTE,
face->glyph->bitmap.buffer
);
//set texture options
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
//Now store character for later use
Character character =
{
texture,
glm::ivec2(face->glyph->bitmap.width, face->glyph->bitmap.rows),
glm::ivec2(face->glyph->bitmap_left, face->glyph->bitmap_top),
face->glyph->advance.x,
};
Characters.insert(std::pair<GLchar, Character>(c, character));
}
glBindTexture(GL_TEXTURE_2D, 0);
//destroy FreeType once we're finished
FT_Done_Face(face);
FT_Done_FreeType(ft);
}
In my Game class I have an initialise function that contains these lines of code:
Text = new TextRenderer(this->Width, this->Height);
Text->Load("fonts/OCRAEXT.TTF", 24);
The problem is that when I try to run the standalone .exe, I get the message "ERROR::FREETYPE: Failed to load font" and the .exe. stops running. I've tried to debug this and I get a message that says "unhandled exception at 0x00730072 in Game.exe. 0xC0000005: Access violation executing location 0x00730072."
The breakpoint points to this line of code:
FT_Set_Pixel_Sizes(face, 0, fontSize);
I've tried stepping through the code to figure out the problem, but little made sense. Could someone please explain what could be the problem?
Upvotes: 1
Views: 2575
Reputation: 162164
FT_New_Face
expects a path in the file system. PE resources are not located in the filesystem, hence trying to locate the file fails and you get this error.
You have to use FT_New_Memory_Face
instead; the memory location of the resource can be retrieved using the Resource API (link to MSDN). Instead of using LoadLibrary
use GetModuleHandle(NULL)
to retrieve a handle to the PE image of the process.
Upvotes: 2