From c963859017e11e1e7b0ca204b8d9bd336eeba508 Mon Sep 17 00:00:00 2001
From: fjebaker <fergusbkr@gmail.com>
Date: Sat, 8 Jun 2024 14:25:31 +0100
Subject: [PATCH] fix: enormously reduce allocations in composite disc tracing

---
 src/tracing/radiative-transfer-problem.jl | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/tracing/radiative-transfer-problem.jl b/src/tracing/radiative-transfer-problem.jl
index e10bfb3f..353b58d2 100644
--- a/src/tracing/radiative-transfer-problem.jl
+++ b/src/tracing/radiative-transfer-problem.jl
@@ -65,20 +65,21 @@ function _intensity_delta(
     m,
     x,
     k::AbstractArray{T},
-    geometry::CompositeGeometry,
+    geometry::CompositeGeometry{K,D},
     within,
     I,
     ν₀,
     r_isco,
     λ,
-) where {T}
-    total::T = zero(T)
-    for i in eachindex(geometry.geometry)
-        total += _intensity_delta(
+) where {T,K,D}
+    indices = (length(D.parameters)...,)
+    sum(zip(geometry.geometry, indices)) do args
+        geom, i = args
+        _intensity_delta(
             m,
             x,
             k,
-            geometry.geometry[i],
+            geom,
             within,
             I,
             ν₀,
@@ -87,7 +88,6 @@ function _intensity_delta(
             index = i,
         )
     end
-    total
 end
 
 function _intensity_delta(