Abstract glyph rendering, poorly

Adds a QuadRenderer class that actually only works with glyphs for now.
Manually place a few glyphs to demonstrate that it works.
This commit is contained in:
Joe Wilm 2016-02-24 21:02:21 -08:00
parent cda4952145
commit eac9747a78
1 changed files with 124 additions and 100 deletions

View File

@ -39,55 +39,18 @@ fn main() {
}
let rasterizer = text::Rasterizer::new();
let glyph_j = rasterizer.get_glyph(180., 'J');
let tex = AlphaTexture::new(
glyph_j.width as i32,
glyph_j.height as i32,
glyph_j.buf.as_ptr() as *const _
);
let glyph_R = Glyph::new(&rasterizer.get_glyph(180., 'R'));
let glyph_u = Glyph::new(&rasterizer.get_glyph(180., 'u'));
let glyph_s = Glyph::new(&rasterizer.get_glyph(180., 's'));
let glyph_t = Glyph::new(&rasterizer.get_glyph(180., 't'));
unsafe {
gl::Enable(gl::BLEND);
gl::BlendFunc(gl::SRC_ALPHA, gl::ONE_MINUS_SRC_ALPHA);
gl::Enable(gl::MULTISAMPLE);
}
let mut vao: GLuint = 0;
let mut vbo: GLuint = 0;
let mut ebo: GLuint = 0;
unsafe {
gl::GenVertexArrays(1, &mut vao);
gl::GenBuffers(1, &mut vbo);
gl::GenBuffers(1, &mut ebo);
gl::BindVertexArray(vao);
gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
gl::BufferData(
gl::ARRAY_BUFFER,
(size_of::<f32>() * 4 * 4) as GLsizeiptr,
ptr::null(),
gl::DYNAMIC_DRAW
);
let indices: [u32; 6] = [0, 1, 3,
1, 2, 3];
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, ebo);
gl::BufferData(gl::ELEMENT_ARRAY_BUFFER,
6 * size_of::<u32>() as isize,
indices.as_ptr() as *const _,
gl::STATIC_DRAW);
gl::EnableVertexAttribArray(0);
gl::VertexAttribPointer(0, 4, gl::FLOAT, gl::FALSE, 4 * size_of::<f32>() as i32,
ptr::null());
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
gl::BindVertexArray(0);
}
let program = ShaderProgram::new(width, height);
let renderer = QuadRenderer::new(width, height);
for event in window.wait_events() {
unsafe {
@ -95,7 +58,10 @@ fn main() {
gl::Clear(gl::COLOR_BUFFER_BIT);
}
render(&program, &glyph_j, &tex, vbo, vao, ebo);
renderer.render(&glyph_R, 10.0, 10.0);
renderer.render(&glyph_u, 130.0, 10.0);
renderer.render(&glyph_s, 250.0, 10.0);
renderer.render(&glyph_t, 370.0, 10.0);
window.swap_buffers();
@ -106,55 +72,109 @@ fn main() {
}
}
fn get_rect(glyph: &RasterizedGlyph, x: f32, y: f32) -> Rect<f32> {
struct QuadRenderer {
program: ShaderProgram,
vao: GLuint,
vbo: GLuint,
ebo: GLuint,
}
impl QuadRenderer {
// TODO should probably hand this a transform instead of width/height
pub fn new(width: u32, height: u32) -> QuadRenderer {
let program = ShaderProgram::new(width, height);
let mut vao: GLuint = 0;
let mut vbo: GLuint = 0;
let mut ebo: GLuint = 0;
unsafe {
gl::GenVertexArrays(1, &mut vao);
gl::GenBuffers(1, &mut vbo);
gl::GenBuffers(1, &mut ebo);
gl::BindVertexArray(vao);
gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
gl::BufferData(
gl::ARRAY_BUFFER,
(size_of::<f32>() * 4 * 4) as GLsizeiptr,
ptr::null(),
gl::DYNAMIC_DRAW
);
let indices: [u32; 6] = [0, 1, 3,
1, 2, 3];
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, ebo);
gl::BufferData(gl::ELEMENT_ARRAY_BUFFER,
6 * size_of::<u32>() as isize,
indices.as_ptr() as *const _,
gl::STATIC_DRAW);
gl::EnableVertexAttribArray(0);
gl::VertexAttribPointer(0, 4, gl::FLOAT, gl::FALSE, 4 * size_of::<f32>() as i32,
ptr::null());
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindVertexArray(0);
}
QuadRenderer {
program: program,
vao: vao,
vbo: vbo,
ebo: ebo,
}
}
pub fn render(&self, glyph: &Glyph, x: f32, y: f32) {
self.program.activate();
unsafe {
// set color
gl::Uniform3f(self.program.u_color, 1., 1., 0.5);
}
let rect = get_rect(glyph, x, y);
// top right of character
let vertices: [[f32; 4]; 4] = [
[rect.max_x(), rect.max_y(), 1., 0.], // top-right
[rect.max_x(), rect.min_y(), 1., 1.], // bottom-right
[rect.min_x(), rect.min_y(), 0., 1.], // bottom-left
[rect.min_x(), rect.max_y(), 0., 0.], // top-left
];
unsafe {
bind_mask_texture(glyph.tex_id);
gl::BindVertexArray(self.vao);
gl::BindBuffer(gl::ARRAY_BUFFER, self.vbo);
gl::BufferSubData(
gl::ARRAY_BUFFER,
0,
(4 * 4 * size_of::<f32>()) as isize,
vertices.as_ptr() as *const _
);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, self.ebo);
gl::DrawElements(gl::TRIANGLES, 6, gl::UNSIGNED_INT, ptr::null());
gl::BindVertexArray(0);
gl::BindTexture(gl::TEXTURE_2D, 0);
}
self.program.deactivate();
}
}
fn get_rect(glyph: &Glyph, x: f32, y: f32) -> Rect<f32> {
Rect::new(
Point2D::new(x, y),
Size2D::new(glyph.width as f32, glyph.height as f32)
)
}
/// Render a character
fn render(program: &ShaderProgram, glyph: &RasterizedGlyph, tex: &AlphaTexture, vbo: GLuint,
vao: GLuint, ebo: GLuint)
{
program.activate();
unsafe {
// set color
gl::Uniform3f(program.u_color, 1., 1., 0.5);
}
let rect = get_rect(glyph, 10.0, 10.0);
// top right of character
let vertices: [[f32; 4]; 4] = [
[rect.max_x(), rect.max_y(), 1., 0.], // top-right
[rect.max_x(), rect.min_y(), 1., 1.], // bottom-right
[rect.min_x(), rect.min_y(), 0., 1.], // bottom-left
[rect.min_x(), rect.max_y(), 0., 0.], // top-left
];
unsafe {
bind_mask_texture(tex.id);
gl::BindVertexArray(vao);
gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
gl::BufferSubData(
gl::ARRAY_BUFFER,
0,
(4 * 4 * size_of::<f32>()) as isize,
vertices.as_ptr() as *const _
);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, ebo);
gl::DrawElements(gl::TRIANGLES, 6, gl::UNSIGNED_INT, ptr::null());
gl::BindVertexArray(0);
gl::BindTexture(gl::TEXTURE_2D, 0);
}
program.deactivate();
}
fn bind_mask_texture(id: u32) {
unsafe {
gl::ActiveTexture(gl::TEXTURE0);
@ -284,14 +304,16 @@ impl ShaderProgram {
}
}
struct AlphaTexture {
pub id: GLuint,
pub width: i32,
pub height: i32,
struct Glyph {
tex_id: GLuint,
top: i32,
left: i32,
width: i32,
height: i32,
}
impl AlphaTexture {
pub fn new(width: i32, height: i32, bytes: *const ::std::os::raw::c_void) -> AlphaTexture {
impl Glyph {
pub fn new(rasterized: &RasterizedGlyph) -> Glyph {
let mut id: GLuint = 0;
unsafe {
gl::PixelStorei(gl::UNPACK_ALIGNMENT, 1);
@ -301,12 +323,12 @@ impl AlphaTexture {
gl::TEXTURE_2D,
0,
gl::RED as i32,
width as i32,
height as i32,
rasterized.width as i32,
rasterized.height as i32,
0,
gl::RED,
gl::UNSIGNED_BYTE,
bytes
rasterized.buf.as_ptr() as *const _
);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_S, gl::CLAMP_TO_EDGE as i32);
@ -317,10 +339,12 @@ impl AlphaTexture {
gl::BindTexture(gl::TEXTURE_2D, 0);
}
AlphaTexture {
id: id,
width: width,
height: height,
Glyph {
tex_id: id,
top: rasterized.top as i32,
width: rasterized.width as i32,
height: rasterized.height as i32,
left: rasterized.left as i32,
}
}
}