1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
use std::mem;
use crate::gl;
use crate::gl::types::*;
use crate::renderer;
/// Number of elements of the `textures[]` uniform.
///
/// If the file `graphics.f.glsl` is modified, this value has to be updated.
pub(super) const TEXTURES_ARRAY_SIZE: usize = 16;
/// Sides where the vertex is located.
///
/// * Bit 0 (LSB) is 0 for top and 1 for bottom.
/// * Bit 1 is 0 for left and 1 for right.
#[derive(Debug, Copy, Clone, PartialEq)]
#[repr(u8)]
pub enum VertexSide {
TopLeft = 0b00,
TopRight = 0b10,
BottomLeft = 0b01,
BottomRight = 0b11,
}
/// Vertex data to execute the graphics rendering program.
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct Vertex {
/// Texture associated to the graphic.
pub texture_id: GLuint,
/// Sides where the vertex is located.
pub sides: VertexSide,
/// Column number in the grid where the left vertex is set.
pub column: GLuint,
/// Line where the top vertex is set.
pub line: GLuint,
/// Height, in pixels, of the texture.
pub height: u16,
/// Width, in pixels, of the texture.
pub width: u16,
/// Offset in the x direction.
pub offset_x: u16,
/// Offset in the y direction.
pub offset_y: u16,
/// Height, in pixels, of a single cell when the graphic was added.
pub base_cell_height: f32,
}
/// Sources for the graphics rendering program.
static GRAPHICS_SHADER_F: &str = include_str!("../../../res/graphics.f.glsl");
static GRAPHICS_SHADER_V: &str = include_str!("../../../res/graphics.v.glsl");
/// Graphics rendering program.
#[derive(Debug)]
pub struct GraphicsShaderProgram {
/// Program id.
pub id: GLuint,
/// Uniform of the cell dimensions.
pub u_cell_dimensions: GLint,
/// Uniform of the view dimensions.
pub u_view_dimensions: GLint,
/// Uniform array of the textures.
pub u_textures: Vec<GLint>,
/// Vertex Array Object (VAO) for the fields of `Vertex`.
pub vao: GLuint,
/// Vertex Buffer Object (VBO) to send instances of `Vertex`.
pub vbo: GLuint,
}
impl GraphicsShaderProgram {
pub fn new() -> Result<Self, renderer::ShaderCreationError> {
let vertex_shader = renderer::create_shader(gl::VERTEX_SHADER, GRAPHICS_SHADER_V)?;
let fragment_shader = renderer::create_shader(gl::FRAGMENT_SHADER, GRAPHICS_SHADER_F)?;
let program = renderer::create_program(vertex_shader, fragment_shader)?;
let u_cell_dimensions;
let u_view_dimensions;
let u_textures;
unsafe {
gl::DeleteShader(fragment_shader);
gl::DeleteShader(vertex_shader);
gl::UseProgram(program);
// Uniform locations.
macro_rules! uniform {
($name:literal) => {
gl::GetUniformLocation(
program,
concat!($name, "\0").as_bytes().as_ptr().cast(),
)
};
($fmt:literal, $($arg:tt)+) => {
match format!(concat!($fmt, "\0"), $($arg)+) {
name => gl::GetUniformLocation(
program,
name.as_bytes().as_ptr().cast(),
)
}
};
}
u_cell_dimensions = uniform!("cellDimensions");
u_view_dimensions = uniform!("viewDimensions");
u_textures =
(0..TEXTURES_ARRAY_SIZE).map(|unit| uniform!("textures[{}]", unit)).collect();
gl::UseProgram(0);
}
let (vao, vbo) = define_vertex_attributes();
let shader =
Self { id: program, u_cell_dimensions, u_view_dimensions, u_textures, vao, vbo };
Ok(shader)
}
}
/// Build a Vertex Array Object (VAO) and a Vertex Buffer Object (VBO) for
/// instances of the `Vertex` type.
fn define_vertex_attributes() -> (GLuint, GLuint) {
let mut vao = 0;
let mut vbo = 0;
unsafe {
gl::GenVertexArrays(1, &mut vao);
gl::GenBuffers(1, &mut vbo);
gl::BindVertexArray(vao);
gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
let mut attr_index = 0;
macro_rules! int_attr {
($type:ident, $field:ident) => {
gl::VertexAttribIPointer(
attr_index,
1,
gl::$type,
mem::size_of::<Vertex>() as i32,
memoffset::offset_of!(Vertex, $field) as *const _,
);
attr_index += 1;
};
}
macro_rules! float_attr {
($type:ident, $field:ident) => {
gl::VertexAttribPointer(
attr_index,
1,
gl::$type,
gl::FALSE,
mem::size_of::<Vertex>() as i32,
memoffset::offset_of!(Vertex, $field) as *const _,
);
attr_index += 1;
};
}
int_attr!(UNSIGNED_INT, texture_id);
int_attr!(UNSIGNED_BYTE, sides);
float_attr!(UNSIGNED_INT, column);
float_attr!(UNSIGNED_INT, line);
float_attr!(UNSIGNED_SHORT, height);
float_attr!(UNSIGNED_SHORT, width);
float_attr!(UNSIGNED_SHORT, offset_x);
float_attr!(UNSIGNED_SHORT, offset_y);
float_attr!(FLOAT, base_cell_height);
for index in 0..attr_index {
gl::EnableVertexAttribArray(index);
}
gl::BindVertexArray(0);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
}
(vao, vbo)
}
|
