Tidy networkCurve shaders

Arrays for start/end position/angle, smaller centre position, dynamic
segment count based on max error, calculate distance in tessellation
evaluation, use start/end position directly to avoid rounding errors at
joins.

See https://schneide.blog/2025/05/21/calculating-the-number-of-segments-for-accurate-circle-rendering/

1 files changed, 8 insertions, 14 deletions

diff --git a/gfx/gl/shaders/networkCurve.vert b/gfx/gl/shaders/networkCurve.vert
index 9cf149b..7e363d3 100644
--- a/gfx/gl/shaders/networkCurve.vert
+++ b/gfx/gl/shaders/networkCurve.vert
@@ -1,29 +1,23 @@
 #version 460 core
 
-layout(location = 0) in ivec3 v_apos;
-layout(location = 1) in ivec3 v_bpos;
+layout(location = 0) in ivec3 v_pos[2];
 layout(location = 2) in ivec3 v_centre;
 layout(location = 3) in float v_reps;
-layout(location = 4) in float v_aangle;
-layout(location = 5) in float v_bangle;
+layout(location = 4) in float v_angles[2];
 layout(location = 6) in float v_radius;
 
-flat out ivec3 apos;
-flat out ivec3 bpos;
-flat out ivec3 cpos;
+flat out ivec3 pos[2];
+flat out ivec2 cpos;
 flat out float reps;
-flat out float aangle;
-flat out float bangle;
+flat out float angles[2];
 flat out float radius;
 
 void
 main()
 {
-	apos = v_apos;
-	bpos = v_bpos;
-	cpos = v_centre;
+	pos = v_pos;
+	cpos = v_centre.xy;
 	reps = v_reps;
-	aangle = v_aangle;
-	bangle = v_bangle;
+	angles = v_angles;
 	radius = v_radius;
 }