Workaround to avoid full hang
As the scale factor becomes unreasonably large, the number of subdivisions of an Euler spiral into lines grows, making the flatten stage take too long.
This patch just bounds the number of subdivisions, so it will eventually make progress. It will be slow, but not hang.
A better solution would be to aggressively cull so it only generates geometry inside the viewport, but that is considerably more complicated.
Workaround for #548
diff --git a/crates/shaders/src/cpu/flatten.rs b/crates/shaders/src/cpu/flatten.rs
index cce140d..bd501d3 100644
--- a/crates/shaders/src/cpu/flatten.rs
+++ b/crates/shaders/src/cpu/flatten.rs
@@ -333,7 +333,7 @@
let n_frac = scaled_int;
(n_frac, EspcRobust::Normal)
};
- let n = (n_frac * scale_multiplier).ceil().max(1.0);
+ let n = (n_frac * scale_multiplier).ceil().clamp(1.0, 100.0);
// Flatten line segments
log!("@@@ loop: lines: {n}");
diff --git a/shader/flatten.wgsl b/shader/flatten.wgsl
index 80da188..2126ad3 100644
--- a/shader/flatten.wgsl
+++ b/shader/flatten.wgsl
@@ -434,7 +434,7 @@
let integrand_peak = sqrt(abs(k_peak * (k_peak * dist_scaled + 1.0)));
n_frac = integral * integrand_peak / a;
}
- let n = max(ceil(n_frac * scale_multiplier), 1.0);
+ let n = clamp(ceil(n_frac * scale_multiplier), 1.0, 100.0);
for (var i = 0u; i < u32(n); i++) {
var lp1: vec2f;
if i + 1u == u32(n) && t1 == 1.0 {
