Fix loading danglymesh constraints

Constraints are now read from two separate data regions.

src/engine/graphics/model/mdlreader.cpp

@@ -336,21 +336,23 @@ shared_ptr<ModelNode::TriangleMesh> MdlReader::readMesh(int flags) {
         float displacement = readFloat();
         float tightness = readFloat();
         float period = readFloat();
-        ignore(4); // unknown
+        uint32_t offDanglyVertices = readUint32();
 
         danglyMesh = make_shared<ModelNode::DanglyMesh>();
         danglyMesh->displacement = 0.5f * displacement;  // displacement is allegedly 1/2 meters per unit
         danglyMesh->tightness = tightness;
         danglyMesh->period = period;
 
+        danglyMesh->constraints.resize(constraintArrayDef.count);
         seek(kMdlDataOffset + constraintArrayDef.offset);
         for (uint32_t i = 0; i < constraintArrayDef.count; ++i) {
             float multiplier = readFloat();
+            danglyMesh->constraints[i].multiplier = glm::clamp(multiplier / 255.0f, 0.0f, 1.0f);
+        }
+        seek(kMdlDataOffset + offDanglyVertices);
+        for (uint32_t i = 0; i < constraintArrayDef.count; ++i) {
             vector<float> positionValues(readFloatArray(3));
-            ModelNode::DanglyMeshConstraint constraint;
-            constraint.multiplier = glm::clamp(multiplier / 255.0f, 0.0f, 1.0f);
-            constraint.position = glm::make_vec3(&positionValues[0]);
-            danglyMesh->constraints.push_back(move(constraint));
+            danglyMesh->constraints[i].position = glm::make_vec3(&positionValues[0]);
         }
 
     } else if (flags & NodeFlags::aabb) {

src/engine/graphics/shader/shaders_common.cpp

@@ -389,7 +389,8 @@ void main() {
             (uBones[i4] * normal) * w4;
 
     } else if (isFeatureEnabled(FEATURE_DANGLYMESH)) {
-        vec3 maxStride = vec3(uDanglymeshDisplacement * uDanglymeshConstraints[gl_VertexID / 4][gl_VertexID % 4]);
+        float multiplier = uDanglymeshConstraints[gl_VertexID / 4][gl_VertexID % 4];
+        vec3 maxStride = vec3(multiplier * uDanglymeshDisplacement);
         vec3 stride = clamp(uDanglymeshStride.xyz, -maxStride, maxStride);
         position += vec4(stride, 0.0);
     }

src/engine/scene/node/meshnode.cpp

@@ -353,8 +353,7 @@ void MeshSceneNode::drawSingle(bool shadowPass) {
             uniforms.combined.featureMask |= UniformFeatureFlags::danglymesh;
             uniforms.danglymesh->stride = glm::vec4(_danglymeshAnimation.stride, 0.0f);
             uniforms.danglymesh->displacement = danglyMesh->displacement;
-            size_t i = 0;
-            for (i = 0; i < danglyMesh->constraints.size(); ++i) {
+            for (size_t i = 0; i < danglyMesh->constraints.size(); ++i) {
                 uniforms.danglymesh->constraints[i / 4][i % 4] = danglyMesh->constraints[i].multiplier;
             }
         }

src/engine/scene/node/meshnode.h

@@ -66,7 +66,7 @@ private:
 
     struct DanglymeshAnimation {
         glm::vec3 force { 0.0f }; /**< net force applied to this scene node */
-        glm::vec3 stride { 0.0f }; /**< how far have vertices traveled from the rest position? */
+        glm::vec3 stride { 0.0f }; /**< how far have vertices traveled from the rest position in object space */
     } _danglymeshAnimation;
 
     const ModelSceneNode *_model;