From 20f90712fcf020ad847af0edc5ffe556c3da8aee Mon Sep 17 00:00:00 2001
From: Michal Dybizbanski <michal.dybizbanski@creoox.com>
Date: Fri, 27 Dec 2024 14:57:07 +0100
Subject: [PATCH] XCD-196 Sort normalFillTransparentBin drawables by their
 distance from the eye before draw calls

---
 src/viewer/scene/webgl/Renderer.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/viewer/scene/webgl/Renderer.js b/src/viewer/scene/webgl/Renderer.js
index 0c483c5afe..33541a6c18 100644
--- a/src/viewer/scene/webgl/Renderer.js
+++ b/src/viewer/scene/webgl/Renderer.js
@@ -11,6 +11,8 @@ import {SAODepthLimitedBlurRenderer} from "./sao/SAODepthLimitedBlurRenderer.js"
 import {RenderBufferManager} from "./RenderBufferManager.js";
 import {getExtension} from "./getExtension.js";
 
+const vec3_0 = math.vec3([0,0,0]);
+
 /**
  * @private
  */
@@ -713,9 +715,11 @@ const Renderer = function (scene, options) {
             // Transparent color fill
 
             if (normalFillTransparentBinLen > 0) {
+                const eye = frameCtx.pickOrigin || scene.camera.eye;
+                const byDist = normalFillTransparentBin.map(d => ({ drawable: d, distSq: math.distVec3(d.origin || vec3_0, eye) }));
+                byDist.sort((a, b) => b.distSq - a.distSq);
                 for (i = 0; i < normalFillTransparentBinLen; i++) {
-                    drawable = normalFillTransparentBin[i];
-                    drawable.drawColorTransparent(frameCtx);
+                    byDist[i].drawable.drawColorTransparent(frameCtx);
                 }
             }