Struct stb_truetype::FontInfo
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[src]
pub struct FontInfo<Data: Deref<Target=[u8]>> {
// some fields omitted
}Methods
impl<Data: Deref<Target=[u8]>> FontInfo<Data>
fn new(data: Data, fontstart: usize) -> Option<FontInfo<Data>>
Given an offset into the file that defines a font, this function builds the necessary cached info for the rest of the system.
fn get_num_glyphs(&self) -> u32
fn find_glyph_index(&self, unicode_codepoint: u32) -> u32
If you're going to perform multiple operations on the same character and you want a speed-up, call this function with the character you're going to process, then use glyph-based functions instead of the codepoint-based functions.
fn get_codepoint_shape(&self, unicode_codepoint: u32) -> Option<Vec<Vertex>>
Returns the series of vertices encoding the shape of the glyph for this codepoint.
The shape is a series of countours. Each one starts with a moveto, then consists of a series of mixed lineto and curveto segments. A lineto draws a line from previous endpoint to its x,y; a curveto draws a quadratic bezier from previous endpoint to its x,y, using cx,cy as the bezier control point.
fn get_glyph_box(&self, glyph_index: u32) -> Option<Rect<i16>>
Like get_codepoint_box, but takes a glyph index. Use this if you have cached the glyph index for
a codepoint.
fn get_codepoint_box(&self, codepoint: u32) -> Option<Rect<i16>>
Gets the bounding box of the visible part of the glyph, in unscaled coordinates
fn is_glyph_empty(&self, glyph_index: u32) -> bool
returns true if nothing is drawn for this glyph
fn get_glyph_shape(&self, glyph_index: u32) -> Option<Vec<Vertex>>
Like get_codepoint_shape, but takes a glyph index instead. Use this if you have cached the
glyph index for a codepoint.
fn get_glyph_h_metrics(&self, glyph_index: u32) -> HMetrics
like get_codepoint_h_metrics, but takes a glyph index instead. Use this if you have cached the
glyph index for a codepoint.
fn get_glyph_kern_advance(&self, glyph_1: u32, glyph_2: u32) -> i32
like get_codepoint_kern_advance, but takes glyph indices instead. Use this if you have cached the
glyph indices for the codepoints.
fn get_codepoint_kern_advance(&self, cp1: u32, cp2: u32) -> i32
an additional amount to add to the 'advance' value between cp1 and cp2
fn get_codepoint_h_metrics(&self, codepoint: u32) -> HMetrics
left_side_bearing is the offset from the current horizontal position to the left edge of the character
advance_width is the offset from the current horizontal position to the next horizontal position
these are expressed in unscaled coordinates
fn get_v_metrics(&self) -> VMetrics
ascent is the coordinate above the baseline the font extends; descent
is the coordinate below the baseline the font extends (i.e. it is typically negative)
line_gap is the spacing between one row's descent and the next row's ascent...
so you should advance the vertical position by ascent - descent + line_gap
these are expressed in unscaled coordinates, so you must multiply by
the scale factor for a given size
fn get_bounding_box(&self) -> Rect<i16>
the bounding box around all possible characters
fn scale_for_pixel_height(&self, height: f32) -> f32
computes a scale factor to produce a font whose "height" is 'pixels' tall. Height is measured as the distance from the highest ascender to the lowest descender; in other words, it's equivalent to calling GetFontVMetrics and computing: scale = pixels / (ascent - descent) so if you prefer to measure height by the ascent only, use a similar calculation.
fn scale_for_mapping_em_to_pixels(&self, pixels: f32) -> f32
computes a scale factor to produce a font whose EM size is mapped to
pixels tall. This is probably what traditional APIs compute, but
I'm not positive.
fn get_glyph_bitmap_box_subpixel(&self, glyph: u32, scale_x: f32, scale_y: f32, shift_x: f32, shift_y: f32) -> Option<Rect<i32>>
like get_codepoint_bitmap_box_subpixel, but takes a glyph index instead of a codepoint.
fn get_glyph_bitmap_box(&self, glyph: u32, scale_x: f32, scale_y: f32) -> Option<Rect<i32>>
like get_codepoint_bitmap_box, but takes a glyph index instead of a codepoint.
fn get_codepoint_bitmap_box_subpixel(&self, codepoint: u32, scale_x: f32, scale_y: f32, shift_x: f32, shift_y: f32) -> Option<Rect<i32>>
same as get_codepoint_bitmap_box, but you can specify a subpixel shift for the character
fn get_codepoint_bitmap_box(&self, codepoint: u32, scale_x: f32, scale_y: f32) -> Option<Rect<i32>>
get the bounding box of the bitmap centered around the glyph origin; so the bitmap width is x1-x0, height is y1-y0, and location to place the bitmap top left is (left_side_bearing*scale, y0). (Note that the bitmap uses y-increases-down, but the shape uses y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)