Module vxdraw::text

Methods and types to control text rendering

Example - Drawing centered text

use vxdraw::{prelude::*, text, void_logger, Deg, Matrix4, ShowWindow, VxDraw};
const DEJAVU: &[u8] = include_bytes!["../fonts/DejaVuSans.ttf"];
fn main() {
    #[cfg(feature = "doctest-headless")]
    let mut vx = VxDraw::new(void_logger(), ShowWindow::Headless1k);
    #[cfg(not(feature = "doctest-headless"))]
    let mut vx = VxDraw::new(void_logger(), ShowWindow::Enable);

    // Create a new layer. A layer consists of a font file and some options
    let mut layer = vx.text().add_layer(DEJAVU, text::LayerOptions::new());

    // Create a new piece of text. We use the origin to center the text. The origin spans
    // between 0 and 1, where 0 is the left-most side of the entire text section, and 1 the
    // right-most. The same goes for the top and bottom respectively. Note that values outside
    // of 0 to 1 are allowed, and define the origin of transformations on that text.
    vx.text().add(
        &mut layer,
        "This text shall be\ncentered, as a whole,\nbut each line is not centered individually",
        text::TextOptions::new().font_size(40.0).origin((0.5, 0.5)),
    );

    vx.draw_frame();

    #[cfg(not(feature = "doctest-headless"))]
    std::thread::sleep(std::time::Duration::new(3, 0));
}

Example - Textured text

Text itself does not directly support textures, but by using blending modes we can overlay a texture onto the text.

use vxdraw::{prelude::*, blender, dyntex::{Filter, ImgData, LayerOptions, Sprite}, quads, text, void_logger, Deg, Matrix4, ShowWindow, VxDraw};
fn main() {
    static FOREST: &ImgData = &ImgData::PNGBytes(include_bytes!["../images/testure.png"]);
    const DEJAVU: &[u8] = include_bytes!["../fonts/DejaVuSans.ttf"];

    #[cfg(feature = "doctest-headless")]
    let mut vx = VxDraw::new(void_logger(), ShowWindow::Headless1k);
    #[cfg(not(feature = "doctest-headless"))]
    let mut vx = VxDraw::new(void_logger(), ShowWindow::Enable);

    let clear_alpha = vx.quads().add_layer(&quads::LayerOptions::new().blend(|x| {
        x.alpha(blender::BlendOp::Add {
            src: blender::BlendFactor::Zero,
            dst: blender::BlendFactor::Zero,
        })
    })
    .fixed_perspective(Matrix4::identity()));

    let text =  vx.text().add_layer(DEJAVU, text::LayerOptions::new().blend(|x| {
        x.alpha(blender::BlendOp::Add {
            src: blender::BlendFactor::One,
            dst: blender::BlendFactor::Zero,
        })
    }));

    let texture = vx.dyntex().add_layer(
        FOREST,
        &LayerOptions::new().blend(|x| {
            x.colors(blender::BlendOp::Add {
                src: blender::BlendFactor::DstAlpha,
                dst: blender::BlendFactor::OneMinusDstAlpha,
            })
        })
        .filter(Filter::Linear),
    );

    vx.quads().add(&clear_alpha, quads::Quad::new());
    vx.text().add(&text, "This is\ntextured text", text::TextOptions::new()
        .origin((0.5, 0.5))
        .font_size(120.0));
    vx.dyntex().add(&texture, Sprite::new().scale(1.0));

    vx.draw_frame();
    #[cfg(not(feature = "doctest-headless"))]
    std::thread::sleep(std::time::Duration::new(3, 0));
}

Structs

Handle	Handle to a piece of text
Layer	Handle to a layer (a single glyph store/font)
LayerOptions	Options for this text layer
TextOptions	Options when adding a text
Texts	Accessor object to all text

Enums

Filter	Specify filter options
FragmentShader	Enum describing which fragment shader to use
VertexShader	Enum describing which vertex shader to use