我编写了一个使用FreeType将文本呈现到窗口上的应用程序。我已经构建了调试和发布版本,都可以从Visual Studio 2015正常运行。我已经设置了运行时库来链接到/ MDd。我还将字体OCRAEXT.TTF包含在资源文件中。
这是使用FreeType的代码:
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);
}
在我的Game类中,我具有一个初始化函数,其中包含以下代码行:
Text = new TextRenderer(this->Width, this->Height);
Text->Load("fonts/OCRAEXT.TTF", 24);
问题是当我尝试运行独立的.exe时,出现消息“ ERROR :: FREETYPE:无法加载字体”和.exe。停止运行。我尝试调试此问题,但收到一条消息,内容为“ Game.exe中0x00730072的未处理异常。0xC0000005:执行位置0x00730072的访问冲突。”
断点指向以下代码行:
FT_Set_Pixel_Sizes(face, 0, fontSize);
我试图逐步检查代码以找出问题所在,但没有什么意义。有人可以解释可能是什么问题吗?
最佳答案
FT_New_Face
需要文件系统中的路径。 PE资源不在文件系统中,因此尝试查找文件失败,并且出现此错误。
您必须使用FT_New_Memory_Face
代替;资源的存储位置可以使用Resource API (link to MSDN)检索。代替使用LoadLibrary
,使用GetModuleHandle(NULL)
检索进程的PE映像的句柄。
关于c++ - 为什么Freetype无法在我的.exe中加载字体,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/36320542/