Hey,
I've been making my own wrapper around Freetype2 for OpenGL. However, I can't seem to easily fix this bug...it's bugging me ^^
Whenever I render the Arial font at 13 pixels height, the 'i' seems to be too high or w/e happens...this only happens when I use the Smooth feature of my wrapper, the Sharp feature works fine.
Examples:
14 pixels smooth
13 pixels sharp
13 pixels smooth
This is the code I use (without error handling):
FT_Load_Char(face, character, FT_LOAD_RENDER);
FT_GlyphSlot &glyph = face->glyph;
FT_Glyph bbox_glyph;
FT_Get_Glyph(glyph, &bbox_glyph);
FT_BBox bbox;
FT_Glyph_Get_CBox(bbox_glyph, FT_GLYPH_BBOX_TRUNCATE, &bbox);
int width = pow2(glyph->bitmap.width);
int height = pow2(glyph->bitmap.rows);
if (width && height) // not a space character
{
GLuint texture = 0;
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
GLubyte *buffer = NULL;
if (_sharpness == Sharpness::Smooth)
{
buffer = new GLubyte[height * width];
memset(buffer, 0x00, height * width);
for (int j = 0; j < glyph->bitmap.rows; j++)
{
memcpy(buffer + (j * width), glyph->bitmap.buffer + (j * glyph->bitmap.pitch), glyph->bitmap.pitch);
}
glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA8, width, height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, buffer);
}
else if (_sharpness == Sharpness::Sharp)
{
buffer = new GLubyte[height * width * 2];
memset(buffer, 0x00, height * width * 2);
for (int j = 0; j < glyph->bitmap.rows; j++)
{
for (int i = 0; i < glyph->bitmap.pitch; i++)
{
buffer[(j * width * 2) + (i * 2)] = buffer[(j * width * 2) + (i * 2) + 1] = glyph->bitmap.buffer[(j * glyph->bitmap.pitch) + i];
}
}
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, buffer);
}
delete[] buffer;
}
// when drawing I use something like
glBindTexture(GL_TEXTURE_2D, character.texture);
glBegin(GL_QUADS);
glTexCoord2d(0, 0); glVertex2f(0, 0);
glTexCoord2d(0, (float) glyph->bitmap.rows / (float) height); glVertex2f(0, glyph->bitmap.rows);
glTexCoord2d((float) glyph->bitmap.pitch / (float) width, (float) glyph->bitmap.rows / (float) height); glVertex2f(glyph->bitmap.pitch, glyph->bitmap.rows);
glTexCoord2d((float) glyph->bitmap.pitch / (float) width, 0); glVertex2f(glyph->bitmap.pitch, 0);
glEnd();
What could possibly be wrong in the pixel copying (since I guess it's the pixel copying part, it only applies to Smooth not Sharp)?
Thanks in advance.
