From bc2ae4b512b8bc7a2b61dd24d9685289453681c5 Mon Sep 17 00:00:00 2001
From: Sébastien Crozet <developer@crozet.re>
Date: Fri, 22 Apr 2022 15:45:53 +0200
Subject: Add a basic lines-based debug-renderer

---
 .../debug_render_pipeline/debug_render_backend.rs  | 66 ++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 src/pipeline/debug_render_pipeline/debug_render_backend.rs

(limited to 'src/pipeline/debug_render_pipeline/debug_render_backend.rs')

diff --git a/src/pipeline/debug_render_pipeline/debug_render_backend.rs b/src/pipeline/debug_render_pipeline/debug_render_backend.rs
new file mode 100644
index 0000000..27a67e4
--- /dev/null
+++ b/src/pipeline/debug_render_pipeline/debug_render_backend.rs
@@ -0,0 +1,66 @@
+use crate::dynamics::{
+    ImpulseJoint, ImpulseJointHandle, Multibody, MultibodyLink, RigidBody, RigidBodyHandle,
+};
+use crate::geometry::Collider;
+use crate::math::{Isometry, Point, Real, Vector};
+use crate::prelude::{ColliderHandle, MultibodyJointHandle};
+use na::Scale;
+
+#[derive(Copy, Clone)]
+pub enum DebugRenderObject<'a> {
+    RigidBody(RigidBodyHandle, &'a RigidBody),
+    Collider(ColliderHandle, &'a Collider),
+    ImpulseJoint(ImpulseJointHandle, &'a ImpulseJoint),
+    MultibodyJoint(MultibodyJointHandle, &'a Multibody, &'a MultibodyLink),
+    Other,
+}
+
+pub trait DebugRenderBackend {
+    fn draw_line(
+        &mut self,
+        object: DebugRenderObject,
+        a: Point<Real>,
+        b: Point<Real>,
+        color: [f32; 4],
+    );
+
+    fn draw_polyline(
+        &mut self,
+        object: DebugRenderObject,
+        vertices: &[Point<Real>],
+        indices: &[[u32; 2]],
+        transform: &Isometry<Real>,
+        scale: &Vector<Real>,
+        color: [f32; 4],
+    ) {
+        for idx in indices {
+            let a = transform * (Scale::from(*scale) * vertices[idx[0] as usize]);
+            let b = transform * (Scale::from(*scale) * vertices[idx[1] as usize]);
+            self.draw_line(object, a, b, color);
+        }
+    }
+
+    fn draw_line_strip(
+        &mut self,
+        object: DebugRenderObject,
+        vertices: &[Point<Real>],
+        transform: &Isometry<Real>,
+        scale: &Vector<Real>,
+        color: [f32; 4],
+        closed: bool,
+    ) {
+        for vtx in vertices.windows(2) {
+            let a = transform * (Scale::from(*scale) * vtx[0]);
+            let b = transform * (Scale::from(*scale) * vtx[1]);
+            self.draw_line(object, a, b, color);
+        }
+
+        if closed {
+            if vertices.len() > 2 {
+                let a = transform * (Scale::from(*scale) * vertices[0]);
+                let b = transform * (Scale::from(*scale) * vertices.last().unwrap());
+                self.draw_line(object, a, b, color);
+            }
+        }
+    }
+}
-- 
cgit 


From 65824e74f3a949343059b3bf5ab51bc7920f416d Mon Sep 17 00:00:00 2001
From: Sébastien Crozet <developer@crozet.re>
Date: Thu, 28 Apr 2022 17:30:35 +0200
Subject: Add comments for the debug-renderer

---
 .../debug_render_pipeline/debug_render_backend.rs       | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

(limited to 'src/pipeline/debug_render_pipeline/debug_render_backend.rs')

diff --git a/src/pipeline/debug_render_pipeline/debug_render_backend.rs b/src/pipeline/debug_render_pipeline/debug_render_backend.rs
index 27a67e4..4fa86e4 100644
--- a/src/pipeline/debug_render_pipeline/debug_render_backend.rs
+++ b/src/pipeline/debug_render_pipeline/debug_render_backend.rs
@@ -6,16 +6,31 @@ use crate::math::{Isometry, Point, Real, Vector};
 use crate::prelude::{ColliderHandle, MultibodyJointHandle};
 use na::Scale;
 
+/// The object currently being rendered by the debug-renderer.
 #[derive(Copy, Clone)]
 pub enum DebugRenderObject<'a> {
+    /// A rigid-body is being rendered.
     RigidBody(RigidBodyHandle, &'a RigidBody),
+    /// A collider is being rendered.
     Collider(ColliderHandle, &'a Collider),
+    /// An impulse-joint is being rendered.
     ImpulseJoint(ImpulseJointHandle, &'a ImpulseJoint),
+    /// A multibody joint is being rendered.
     MultibodyJoint(MultibodyJointHandle, &'a Multibody, &'a MultibodyLink),
+    /// Another element is being rendered.
     Other,
 }
 
+/// Trait implemented by graphics backends responsible for rendering the physics scene.
+///
+/// The only thing that is required from the graphics backend is to be able to render
+/// a colored line. Note that the color is only a suggestion and is computed from the
+/// `DebugRenderStyle`. The backend is free to apply its own style, for example based on
+/// the `object` being rendered.
 pub trait DebugRenderBackend {
+    /// Draws a colored line.
+    ///
+    /// Note that this method can be called multiple time for the same `object`.
     fn draw_line(
         &mut self,
         object: DebugRenderObject,
@@ -24,6 +39,7 @@ pub trait DebugRenderBackend {
         color: [f32; 4],
     );
 
+    /// Draws a set of line.
     fn draw_polyline(
         &mut self,
         object: DebugRenderObject,
@@ -40,6 +56,7 @@ pub trait DebugRenderBackend {
         }
     }
 
+    /// Draws a chain of line.
     fn draw_line_strip(
         &mut self,
         object: DebugRenderObject,
-- 
cgit