From b215eeadfa1556c931af470e6d3aeaacbf9d7ebb Mon Sep 17 00:00:00 2001
From: devZoGok <nenkokeko@yandex.com>
Date: Thu, 21 Jan 2021 21:15:31 +0200
Subject: [PATCH] more precise vert weight distribution

---
 mesh.cpp          |  2 +-
 texture.vert      | 35 +++++++++++++++++++++--------------
 vbModelReader.cpp | 16 ++++++++++++++--
 3 files changed, 36 insertions(+), 17 deletions(-)

diff --git a/mesh.cpp b/mesh.cpp
index 76e7a51..009f5f5 100755
--- a/mesh.cpp
+++ b/mesh.cpp
@@ -170,7 +170,7 @@ namespace vb01{
 			Vector3 posePos = bone->getPosePos();
 			Quaternion poseRot = bone->getPoseRot();
 			Vector3 rotAxis = poseRot.getAxis(); 
-			rotAxis = boneAxis[0] * rotAxis.x + boneAxis[1] * rotAxis.y + boneAxis[2] * rotAxis.z;
+			rotAxis = (boneAxis[0] * rotAxis.x + boneAxis[1] * rotAxis.y + boneAxis[2] * rotAxis.z).norm();
 			Vector3 trans = boneAxis[0] * posePos.x + boneAxis[1] * posePos.y + boneAxis[2] * posePos.z;
 			Vector3 scale = bone->getPoseScale();
 			Vector3 bonePos = bone->getBoneSpaceRestPos(skeleton->getRootBone());
diff --git a/texture.vert b/texture.vert
index 2596aec..5675da8 100755
--- a/texture.vert
+++ b/texture.vert
@@ -30,34 +30,40 @@ uniform mat4 model;
 uniform mat4 view;
 uniform mat4 proj;
 
+mat4 createMatrix(float angle, vec3 axis){
+	mat4 rotMat;
+
+	float s = sin(angle);
+	float c = cos(angle);
+	float oc = 1.0 - c;
+
+	rotMat[0] = vec4(oc * axis.x * axis.x + c,oc * axis.x * axis.y + axis.z * s,oc * axis.z * axis.x - axis.y * s, 0.0);                              
+	rotMat[1] = vec4(oc * axis.x * axis.y - axis.z * s,oc * axis.y * axis.y + c,oc * axis.y * axis.z + axis.x * s, 0.0);                              
+	rotMat[2] = vec4(oc * axis.z * axis.x + axis.y * s,oc * axis.y * axis.z - axis.x * s,oc * axis.z * axis.z + c, 0.0);                              
+	rotMat[3] = vec4(0, 0, 0, 1);
+
+	return rotMat;
+}
+
 void main(){
-	vec4 vertPos=vec4(aPos,1);
+	vec4 vertPos = vec4(aPos, 1);
 	if(animated){
 		for(int i = 0; i < numBones; i++){
-			Bone bone = bones[i];
 			float weight = 0;
-
 			for(int j = 0; j < numMaxInfluences; j++){
-				if(bone.vertGroup == aBoneIndices[j])
+				if(bones[i].vertGroup == aBoneIndices[j])
 					weight = aWeight[j];
 			}	
 
-			while(bone.parent!=-1){
+			Bone bone = bones[i];
+			while(bone.parent != -1){
 				float angle = weight * bone.angle;
 				vec3 trans = bone.trans;
 				vec3 axis = bone.rotAxis;
 				vec3 scale = bone.scale;
 				vec4 bonePos = vec4(bone.pos, 1);
 			
-				float s = sin(angle);
-				float c = cos(angle);
-				float oc = 1.0 - c;
-			
-				mat4 rotMat;
-				rotMat[0] = vec4(oc * axis.x * axis.x + c,oc * axis.x * axis.y + axis.z * s,oc * axis.z * axis.x - axis.y * s, 0.0);                              
-				rotMat[1] = vec4(oc * axis.x * axis.y - axis.z * s,oc * axis.y * axis.y + c,oc * axis.y * axis.z + axis.x * s, 0.0);                              
-				rotMat[2] = vec4(oc * axis.z * axis.x + axis.y * s,oc * axis.y * axis.z - axis.x * s,oc * axis.z * axis.z + c, 0.0);                              
-				rotMat[3] = vec4(0, 0, 0, 1);
+				mat4 rotMat = createMatrix(angle, axis);
 				
 				vertPos += -(vertPos - bonePos) + rotMat * (vertPos - bonePos);
 				vec4 vertToBone = vec4(vertPos.xyz - bonePos.xyz, 1);
@@ -65,6 +71,7 @@ void main(){
 				vertPos.xyz += weight * trans;
 
 				bone = bones[bone.parent];
+
 			}
 		}
 	}
diff --git a/vbModelReader.cpp b/vbModelReader.cpp
index 51aea26..153c9de 100644
--- a/vbModelReader.cpp
+++ b/vbModelReader.cpp
@@ -288,8 +288,20 @@ namespace vb01{
 			vertPos.push_back(vPos);
 			vertNorm.push_back(vNorm);
 
-			for(int j = 0; j < numBones; j++)
-				vertWeights.push_back(atof(data[6 + j].c_str()));
+			float weightCoefs[numBones];
+			for(int i = 0; i < numBones; i++)
+				weightCoefs[i] = atof(data[6 + i].c_str());
+
+			int numPosWeights = 0;
+			float sumWeightCoefs = 0;
+			for(int i = 0; i < numBones; i++)
+				if(weightCoefs[i] > 0){
+					sumWeightCoefs += weightCoefs[i];
+				}
+
+			float root = 1. / sumWeightCoefs;
+			for(int i = 0; i < numBones; i++)
+				vertWeights.push_back(root * weightCoefs[i]);
 		}
 	}