From 575ac0525c6ee2fab81a4847adb6399807996a17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ga=C3=ABtan=20Brochard?= <gaetan.brochard@ekino.com>
Date: Thu, 2 Dec 2021 02:10:16 +0100
Subject: [PATCH] feat: Setup SDL - 0002

---
 Cargo.toml    |  9 +++++++++
 src/main.rs   | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/render.rs | 34 ++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)
 create mode 100644 Cargo.toml
 create mode 100644 src/main.rs
 create mode 100644 src/render.rs

diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..b2b99c6
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "metagraphs_poc"
+version = "0.1.0"
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+sdl2 = "0.35.1"
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..6e5346b
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,49 @@
+extern crate sdl2;
+
+mod render;
+
+use render::render;
+use sdl2::event::Event;
+use sdl2::keyboard::Keycode;
+use sdl2::pixels::PixelFormatEnum;
+use sdl2::surface::Surface;
+
+fn main() {
+    let sdl_context = sdl2::init().unwrap();
+    let video_subsystem = sdl_context.video().unwrap();
+    let window = video_subsystem
+        .window("metagraphs proof of concept", 800, 800)
+        .position_centered()
+        .opengl()
+        .build()
+        .unwrap();
+    let mut canvas = window.into_canvas().build().unwrap();
+    let texture_creator = canvas.texture_creator();
+    let mut event_pump = sdl_context.event_pump().unwrap();
+    let mut data = Box::new([255u8; 1_920_000]);
+
+    let mut frame_count: u32 = 0;
+
+    'running: loop {
+        for event in event_pump.poll_iter() {
+            match event {
+                Event::Quit { .. }
+                | Event::KeyDown {
+                    keycode: Some(Keycode::Escape),
+                    ..
+                } => break 'running,
+                _ => {}
+            }
+        }
+
+        render(&mut *data, frame_count);
+        let surface =
+            Surface::from_data(&mut *data, 800, 800, 2400, PixelFormatEnum::RGB24).unwrap();
+        let texture = texture_creator
+            .create_texture_from_surface(surface)
+            .unwrap();
+        canvas.copy(&texture, None, None).unwrap();
+        canvas.present();
+        frame_count += 1;
+    }
+}
diff --git a/src/render.rs b/src/render.rs
new file mode 100644
index 0000000..9adf082
--- /dev/null
+++ b/src/render.rs
@@ -0,0 +1,34 @@
+use std::f64;
+
+use sdl2::pixels::Color;
+
+fn put_pixel(data: &mut [u8], x: usize, y: usize, color: Color) {
+    data[y * 3 * 800 + x * 3] = color.r;
+    data[y * 3 * 800 + x * 3 + 1] = color.g;
+    data[y * 3 * 800 + x * 3 + 2] = color.b;
+}
+
+pub fn render(data: &mut [u8], frame_count: u32) {
+    let time = frame_count as f64 / 60. * 6.28;
+    let ct = f64::cos(time);
+    let st = f64::sin(time);
+    for x in 0..800 {
+        for y in 0..800 {
+            let cx: f64 = f64::cos(st * 1.0 + (x as f64 - 400.) / 39.123 * ct) + 1.;
+            let cy: f64 = f64::cos(ct * 1.1 + (y as f64 - 400.) / 40.123 * st) + 1.;
+            let sx: f64 = f64::sin(ct * 1.2 + (x as f64 - 400.) / 41.123 * ct) + 1.;
+            let sy: f64 = f64::sin(st * 1.3 + (y as f64 - 400.) / 42.123 * st) + 1.;
+            put_pixel(
+                &mut *data,
+                x,
+                y,
+                Color {
+                    r: (cx * 128.) as u8,
+                    g: (cy * sx * 64.) as u8,
+                    b: (sy * 128.) as u8,
+                    a: 0,
+                },
+            );
+        }
+    }
+}