Pass external data to the fragment shader

1 files changed, 32 insertions, 28 deletions

diff --git a/src/main.rs b/src/main.rs
index 5768622..becb510 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,17 +3,12 @@ mod number;
 mod poly;
 
 use lerp::Lerp;
-use number::Number;
 
-use std::thread;
-use std::time::Duration;
 use std::os::raw::c_void;
 use std::ffi::{CString, CStr};
 
 use sdl2::event::Event;
 use sdl2::keyboard::Keycode;
-use sdl2::pixels::Color;
-use sdl2::rect::Rect;
 
 use gl::types::*;
 
@@ -32,11 +27,8 @@ fn shader_from_source(source: &CStr, shader_type: GLenum) -> GLuint {
 }
 
 fn main() {
-    let a = Lerp::new(vec![200.0, 200.0, 200.0]);
-    let b = Lerp::new(vec![100.0, 550.0, 1000.0]);
-    let pa = lerp::lp(a);
-    let pb = lerp::lp(b);
-    let p = poly::gcd(&pa, &pb);
+    let a = lerp::lp(Lerp::new(vec![100.0, 200.0, 800.0]));
+    let b = lerp::lp(Lerp::new(vec![100.0, 550.0, 500.0]));
 
     let sdl_context = sdl2::init().unwrap();
     let video_subsystem = sdl_context.video().unwrap();
@@ -84,42 +76,54 @@ fn main() {
     }
     ".to_vec();
 
-    let fragment_shader_source = b"
+    let fragment_shader_source = String::from(format!("
 #version 410 core
 out vec4 FragColor;
 
-float p1[3] = float[3](200, 400, 1300);
-float p2[3] = float[3](100, 900, -970);
+float pa[{sa}] = float[{sa}]({pa});
+float pb[{sb}] = float[{sb}]({pb});
 float threshold = 0.1;
 
-float eval(float[3] v, float t) {
-  return v[2] * t * t + v[1] * t + v[0];
-}
-
-float inside(vec2 pos) {
+float eval_a(float[{sa}] v, float t) {{
+    float result = 0.0;
+    for (int i = 0; i < {sa}; i++) {{
+      result += v[i] * pow(t, i);
+    }}
+    return result;
+}}
+
+float eval_b(float[{sb}] v, float t) {{
+    float result = 0.0;
+    for (int i = 0; i < {sb}; i++) {{
+      result += v[i] * pow(t, i);
+    }}
+    return result;
+}}
+
+float inside(vec2 pos) {{
   float res = 100;
   float thr = 32;
   float closest = 10000;
   float t = 0.0;
-  while (t < 1.0) {
+  while (t < 1.0) {{
     float step = t + 1.0 / res;
-    vec2 a = vec2(eval(p1, t), eval(p2, t));
-    vec2 b = vec2(eval(p1, step), eval(p2, step));
+    vec2 a = vec2(eval_a(pa, t), eval_b(pb, t));
+    vec2 b = vec2(eval_a(pa, step), eval_b(pb, step));
     vec2 n = vec2(-(b - a).y, (b - a).x);
     float d = dot(a - pos, n) / length(n);
-    if (d < closest) {
+    if (d < closest) {{
       closest = d;
-    }
+    }}
     t = step;
-  }
+  }}
   return 1 - pow(closest / thr, 2);
-}
+}}
 
-void main() {
+void main() {{
   float r = inside(gl_FragCoord.xy);
     FragColor = vec4(r * 0.8, r * 0.2, r, 1.0);
-}
-    ".to_vec();
+}}
+    ", sa = a.degree() + 1, sb = b.degree() + 1, pa = &a, pb = &b)).into_bytes();
 
     let mut vbo: GLuint = 0;
     let mut vao: GLuint = 0;