From b6f33c7052d503244ca4833722531efccce533ff Mon Sep 17 00:00:00 2001
From: luboslenco <lubos.lenco@gmail.com>
Date: Sun, 17 Jan 2021 15:50:42 +0100
Subject: [PATCH] Fix material split for obj import

---
 Sources/arm/io/ImportObj.hx | 31 ++++++++++++++++++++++++++++---
 1 file changed, 28 insertions(+), 3 deletions(-)

diff --git a/Sources/arm/io/ImportObj.hx b/Sources/arm/io/ImportObj.hx
index 3a7ea70e..d655f79a 100644
--- a/Sources/arm/io/ImportObj.hx
+++ b/Sources/arm/io/ImportObj.hx
@@ -56,13 +56,37 @@ class ImportObj {
 								texa1 = parts[j].texa != null ? parts[j].texa : null;
 								inda0 = parts[i].inda;
 								inda1 = parts[j].inda;
+								var voff = Std.int(posa0.length / 4);
+								// Repack merged positions
+								var posa32 = new kha.arrays.Float32Array(Std.int(posa0.length / 4) * 3 + Std.int(posa1.length / 4) * 3);
+								for (k in 0...Std.int(posa0.length / 4)) {
+									posa32[k * 3    ] = posa0[k * 4    ] / 32767 * parts[i].scalePos;
+									posa32[k * 3 + 1] = posa0[k * 4 + 1] / 32767 * parts[i].scalePos;
+									posa32[k * 3 + 2] = posa0[k * 4 + 2] / 32767 * parts[i].scalePos;
+								}
+								for (k in 0...Std.int(posa1.length / 4)) {
+									posa32[voff * 3 + k * 3    ] = posa1[k * 4    ] / 32767 * parts[j].scalePos;
+									posa32[voff * 3 + k * 3 + 1] = posa1[k * 4 + 1] / 32767 * parts[j].scalePos;
+									posa32[voff * 3 + k * 3 + 2] = posa1[k * 4 + 2] / 32767 * parts[j].scalePos;
+								}
+								var scalePos = 0.0;
+								for (k in 0...posa32.length) {
+									var f = Math.abs(posa32[k]);
+									if (scalePos < f) scalePos = f;
+								}
+								var inv = 32767 * (1 / scalePos);
 								var posa = new kha.arrays.Int16Array(posa0.length + posa1.length);
+								for (k in 0...Std.int(posa.length / 4)) {
+									posa[k * 4    ] = Std.int(posa32[k * 3    ] * inv);
+									posa[k * 4 + 1] = Std.int(posa32[k * 3 + 1] * inv);
+									posa[k * 4 + 2] = Std.int(posa32[k * 3 + 2] * inv);
+								}
+								for (k in 0...Std.int(posa0.length / 4)) posa[k * 4 + 3] = posa0[k * 4 + 3];
+								for (k in 0...Std.int(posa1.length / 4)) posa[posa0.length + k * 4 + 3] = posa1[k * 4 + 3];
+								// Merge normals and uvs
 								var nora = new kha.arrays.Int16Array(nora0.length + nora1.length);
 								var texa = (texa0 != null && texa1 != null) ? new kha.arrays.Int16Array(texa0.length + texa1.length) : null;
 								var inda = new kha.arrays.Uint32Array(inda0.length + inda1.length);
-								var voff = Std.int(posa0.length / 4);
-								js.Syntax.code("posa.set(posa0)");
-								js.Syntax.code("posa.set(posa1, posa0.length)");
 								js.Syntax.code("nora.set(nora0)");
 								js.Syntax.code("nora.set(nora1, nora0.length)");
 								if (texa != null) {
@@ -75,6 +99,7 @@ class ImportObj {
 								parts[i].nora = nora;
 								parts[i].texa = texa;
 								parts[i].inda = inda;
+								parts[i].scalePos = scalePos;
 								parts.splice(j, 1);
 							}
 							else j++;