model emitters!

libraries/entities-renderer/src/RenderableParticleEffectEntityItem.cpp

@@ -1,4 +1,4 @@
-//
+//
 //  RenderableParticleEffectEntityItem.cpp
 //  interface/src
 //
@@ -14,6 +14,8 @@
 #include <GeometryCache.h>
 #include <shaders/Shaders.h>
 
+#include <glm/gtx/transform.hpp>
+
 using namespace render;
 using namespace render::entities;
 
@@ -111,6 +113,7 @@ void ParticleEffectEntityRenderer::doRenderUpdateSynchronousTyped(const ScenePoi
         QString compoundShapeURL = entity->getCompoundShapeURL();
         if (_compoundShapeURL != compoundShapeURL) {
             _compoundShapeURL = compoundShapeURL;
+            _hasComputedTriangles = false;
             fetchGeometryResource();
         }
     });
@@ -217,7 +220,8 @@ float importanceSample3DDimension(float startDim) {
 }
 
 ParticleEffectEntityRenderer::CpuParticle ParticleEffectEntityRenderer::createParticle(uint64_t now, const Transform& baseTransform, const particle::Properties& particleProperties,
-                                                                                       const ShapeType& shapeType, const GeometryResource::Pointer& geometryResource) {
+                                                                                       const ShapeType& shapeType, const GeometryResource::Pointer& geometryResource,
+                                                                                       const TriangleInfo& triangleInfo) {
     CpuParticle particle;
 
     const auto& accelerationSpread = particleProperties.emission.acceleration.spread;
@@ -259,7 +263,7 @@ ParticleEffectEntityRenderer::CpuParticle ParticleEffectEntityRenderer::createPa
         } else {
             azimuth = azimuthStart + (TWO_PI + azimuthFinish - azimuthStart) * randFloat();
         }
-        // TODO: azimuth and elevation are only used for ellipsoids, but could be used for other shapes too
+        // TODO: azimuth and elevation are only used for ellipsoids/circles, but could be used for other shapes too
 
         if (emitDimensions == Vectors::ZERO) {
             // Point
@@ -301,7 +305,7 @@ ParticleEffectEntityRenderer::CpuParticle ParticleEffectEntityRenderer::createPa
                     break;
                 }
 
-                case SHAPE_TYPE_CIRCLE: { // FIXME: SHAPE_TYPE_CIRCLE is not exposed to scripts in buildStringToShapeTypeLookup()
+                case SHAPE_TYPE_CIRCLE: {
                     glm::vec2 radii = importanceSample2DDimension(emitRadiusStart) * 0.5f * glm::vec2(emitDimensions.x, emitDimensions.z);
                     float x = radii.x * glm::cos(azimuth);
                     float z = radii.y * glm::sin(azimuth);
@@ -326,7 +330,43 @@ ParticleEffectEntityRenderer::CpuParticle ParticleEffectEntityRenderer::createPa
                     break;
                 }
 
-                case SHAPE_TYPE_COMPOUND:
+                case SHAPE_TYPE_COMPOUND: {
+                    // if we get here we know that geometryResource is loaded
+
+                    size_t index = randFloat() * triangleInfo.totalSamples;
+                    Triangle triangle;
+                    for (size_t i = 0; i < triangleInfo.samplesPerTriangle.size(); i++) {
+                        size_t numSamples = triangleInfo.samplesPerTriangle[i];
+                        if (index < numSamples) {
+                            triangle = triangleInfo.triangles[i];
+                            break;
+                        }
+                        index -= numSamples;
+                    }
+
+                    float edgeLength1 = glm::length(triangle.v1 - triangle.v0);
+                    float edgeLength2 = glm::length(triangle.v2 - triangle.v1);
+                    float edgeLength3 = glm::length(triangle.v0 - triangle.v2);
+
+                    float perimeter = edgeLength1 + edgeLength2 + edgeLength3;
+                    float fraction1 = randFloatInRange(0.0f, 1.0f);
+                    float fractionEdge1 = glm::min(fraction1 * perimeter / edgeLength1, 1.0f);
+                    float fraction2 = fraction1 - edgeLength1 / perimeter;
+                    float fractionEdge2 = glm::clamp(fraction2 * perimeter / edgeLength2, 0.0f, 1.0f);
+                    float fraction3 = fraction2 - edgeLength2 / perimeter;
+                    float fractionEdge3 = glm::clamp(fraction3 * perimeter / edgeLength3, 0.0f, 1.0f);
+
+                    float dim = importanceSample2DDimension(emitRadiusStart);
+                    triangle = triangle * (glm::scale(emitDimensions) * triangleInfo.transform);
+                    glm::vec3 center = (triangle.v0 + triangle.v1 + triangle.v2) / 3.0f;
+                    glm::vec3 v0 = (dim * (triangle.v0 - center)) + center;
+                    glm::vec3 v1 = (dim * (triangle.v1 - center)) + center;
+                    glm::vec3 v2 = (dim * (triangle.v2 - center)) + center;
+
+                    emitPosition = glm::mix(v0, glm::mix(v1, glm::mix(v2, v0, fractionEdge3), fractionEdge2), fractionEdge1);
+                    emitDirection = triangle.getNormal();
+                    break;
+                }
 
                 case SHAPE_TYPE_SPHERE:
                 case SHAPE_TYPE_ELLIPSOID:
@@ -374,13 +414,16 @@ void ParticleEffectEntityRenderer::stepSimulation() {
 
     const auto& modelTransform = getModelTransform();
     if (_emitting && particleProperties.emitting() &&
-        (_shapeType != SHAPE_TYPE_COMPOUND || (_geometryResource && _geometryResource->isLoaded()))) {
+        (shapeType != SHAPE_TYPE_COMPOUND || (geometryResource && geometryResource->isLoaded()))) {
         uint64_t emitInterval = particleProperties.emitIntervalUsecs();
         if (emitInterval > 0 && interval >= _timeUntilNextEmit) {
             auto timeRemaining = interval;
             while (timeRemaining > _timeUntilNextEmit) {
+                if (_shapeType == SHAPE_TYPE_COMPOUND && !_hasComputedTriangles) {
+                    computeTriangles(geometryResource->getHFMModel());
+                }
                 // emit particle
-                _cpuParticles.push_back(createParticle(now, modelTransform, particleProperties, shapeType, geometryResource));
+                _cpuParticles.push_back(createParticle(now, modelTransform, particleProperties, shapeType, geometryResource, _triangleInfo));
                 _timeUntilNextEmit = emitInterval;
                 if (emitInterval < timeRemaining) {
                     timeRemaining -= emitInterval;
@@ -468,3 +511,119 @@ void ParticleEffectEntityRenderer::fetchGeometryResource() {
         _geometryResource = DependencyManager::get<ModelCache>()->getCollisionGeometryResource(hullURL);
     }
 }
+
+// FIXME: this is very similar to Model::calculateTriangleSets
+void ParticleEffectEntityRenderer::computeTriangles(const hfm::Model& hfmModel) {
+    PROFILE_RANGE(render, __FUNCTION__);
+
+    int numberOfMeshes = hfmModel.meshes.size();
+
+    _hasComputedTriangles = true;
+    _triangleInfo.triangles.clear();
+    _triangleInfo.samplesPerTriangle.clear();
+
+    std::vector<float> areas;
+    float minArea = FLT_MAX;
+    AABox bounds;
+
+    for (int i = 0; i < numberOfMeshes; i++) {
+        const HFMMesh& mesh = hfmModel.meshes.at(i);
+
+        const int numberOfParts = mesh.parts.size();
+        for (int j = 0; j < numberOfParts; j++) {
+            const HFMMeshPart& part = mesh.parts.at(j);
+
+            const int INDICES_PER_TRIANGLE = 3;
+            const int INDICES_PER_QUAD = 4;
+            const int TRIANGLES_PER_QUAD = 2;
+
+            // tell our triangleSet how many triangles to expect.
+            int numberOfQuads = part.quadIndices.size() / INDICES_PER_QUAD;
+            int numberOfTris = part.triangleIndices.size() / INDICES_PER_TRIANGLE;
+            int totalTriangles = (numberOfQuads * TRIANGLES_PER_QUAD) + numberOfTris;
+            _triangleInfo.triangles.reserve(_triangleInfo.triangles.size() + totalTriangles);
+            areas.reserve(areas.size() + totalTriangles);
+
+            auto meshTransform = hfmModel.offset * mesh.modelTransform;
+
+            if (part.quadIndices.size() > 0) {
+                int vIndex = 0;
+                for (int q = 0; q < numberOfQuads; q++) {
+                    int i0 = part.quadIndices[vIndex++];
+                    int i1 = part.quadIndices[vIndex++];
+                    int i2 = part.quadIndices[vIndex++];
+                    int i3 = part.quadIndices[vIndex++];
+
+                    // track the model space version... these points will be transformed by the FST's offset, 
+                    // which includes the scaling, rotation, and translation specified by the FST/FBX, 
+                    // this can't change at runtime, so we can safely store these in our TriangleSet
+                    glm::vec3 v0 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i0], 1.0f));
+                    glm::vec3 v1 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i1], 1.0f));
+                    glm::vec3 v2 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i2], 1.0f));
+                    glm::vec3 v3 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i3], 1.0f));
+
+                    Triangle tri1 = { v0, v1, v3 };
+                    Triangle tri2 = { v1, v2, v3 };
+                    _triangleInfo.triangles.push_back(tri1);
+                    _triangleInfo.triangles.push_back(tri2);
+
+                    float area1 = tri1.getArea();
+                    areas.push_back(area1);
+                    if (area1 > EPSILON) {
+                        minArea = std::min(minArea, area1);
+                    }
+
+                    float area2 = tri2.getArea();
+                    areas.push_back(area2);
+                    if (area2 > EPSILON) {
+                        minArea = std::min(minArea, area2);
+                    }
+
+                    bounds += v0;
+                    bounds += v1;
+                    bounds += v2;
+                    bounds += v3;
+                }
+            }
+
+            if (part.triangleIndices.size() > 0) {
+                int vIndex = 0;
+                for (int t = 0; t < numberOfTris; t++) {
+                    int i0 = part.triangleIndices[vIndex++];
+                    int i1 = part.triangleIndices[vIndex++];
+                    int i2 = part.triangleIndices[vIndex++];
+
+                    // track the model space version... these points will be transformed by the FST's offset, 
+                    // which includes the scaling, rotation, and translation specified by the FST/FBX, 
+                    // this can't change at runtime, so we can safely store these in our TriangleSet
+                    glm::vec3 v0 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i0], 1.0f));
+                    glm::vec3 v1 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i1], 1.0f));
+                    glm::vec3 v2 = glm::vec3(meshTransform * glm::vec4(mesh.vertices[i2], 1.0f));
+
+                    Triangle tri = { v0, v1, v2 };
+                    _triangleInfo.triangles.push_back(tri);
+
+                    float area = tri.getArea();
+                    areas.push_back(area);
+                    if (area > EPSILON) {
+                        minArea = std::min(minArea, area);
+                    }
+
+                    bounds += v0;
+                    bounds += v1;
+                    bounds += v2;
+                }
+            }
+        }
+    }
+
+    _triangleInfo.totalSamples = 0;
+    for (auto& area : areas) {
+        size_t numSamples = area / minArea;
+        _triangleInfo.samplesPerTriangle.push_back(numSamples);
+        _triangleInfo.totalSamples += numSamples;
+    }
+
+    glm::vec3 scale = bounds.getScale();
+    _triangleInfo.transform = glm::scale(1.0f / scale) * glm::translate(-bounds.calcCenter());
+}

libraries/entities-renderer/src/RenderableParticleEffectEntityItem.h

@@ -81,8 +81,18 @@ private:
         glm::vec2 spare;
     };
 
+    void computeTriangles(const hfm::Model& hfmModel);
+    bool _hasComputedTriangles{ false };
+    struct TriangleInfo {
+        std::vector<Triangle> triangles;
+        std::vector<size_t> samplesPerTriangle;
+        size_t totalSamples;
+        glm::mat4 transform;
+    } _triangleInfo;
+
     static CpuParticle createParticle(uint64_t now, const Transform& baseTransform, const particle::Properties& particleProperties,
-                                      const ShapeType& shapeType, const GeometryResource::Pointer& geometryResource);
+                                      const ShapeType& shapeType, const GeometryResource::Pointer& geometryResource,
+                                      const TriangleInfo& triangleInfo);
     void stepSimulation();
 
     particle::Properties _particleProperties;

libraries/entities/src/EntityItemProperties.cpp

@@ -127,6 +127,7 @@ void buildStringToShapeTypeLookup() {
     addShapeType(SHAPE_TYPE_SIMPLE_COMPOUND);
     addShapeType(SHAPE_TYPE_STATIC_MESH);
     addShapeType(SHAPE_TYPE_ELLIPSOID);
+    addShapeType(SHAPE_TYPE_CIRCLE);
 }
 
 QHash<QString, MaterialMappingMode> stringToMaterialMappingModeLookup;
@@ -1121,21 +1122,21 @@ EntityPropertyFlags EntityItemProperties::getChangedProperties() const {
  *     Particles are emitted from the portion of the shape that lies between <code>emitRadiusStart</code> and the 
  *     shape's surface.
  * @property {number} polarStart=0 - The angle in radians from the entity's local z-axis at which particles start being emitted 
- *     within the ellipsoid; range <code>0</code> &ndash; <code>Math.PI</code>. Particles are emitted from the portion of the 
+ *     within the shape; range <code>0</code> &ndash; <code>Math.PI</code>. Particles are emitted from the portion of the 
- *     ellipsoid that lies between <code>polarStart<code> and <code>polarFinish</code>.  Only used if <code>shapeType</code> is
+ *     shape that lies between <code>polarStart<code> and <code>polarFinish</code>.  Only used if <code>shapeType</code> is
- *     <code>ellipsoid</code>.
+ *     <code>ellipsoid</code> or <code>sphere</code>.
  * @property {number} polarFinish=0 - The angle in radians from the entity's local z-axis at which particles stop being emitted 
- *     within the ellipsoid; range <code>0</code> &ndash; <code>Math.PI</code>. Particles are emitted from the portion of the 
+ *     within the shape; range <code>0</code> &ndash; <code>Math.PI</code>. Particles are emitted from the portion of the 
- *     ellipsoid that lies between <code>polarStart<code> and <code>polarFinish</code>.  Only used if <code>shapeType</code> is
+ *     shape that lies between <code>polarStart<code> and <code>polarFinish</code>.  Only used if <code>shapeType</code> is
- *     <code>ellipsoid</code>.
+ *     <code>ellipsoid</code> or <code>sphere</code>.
  * @property {number} azimuthStart=-Math.PI - The angle in radians from the entity's local x-axis about the entity's local 
  *     z-axis at which particles start being emitted; range <code>-Math.PI</code> &ndash; <code>Math.PI</code>. Particles are 
- *     emitted from the portion of the ellipsoid that lies between <code>azimuthStart<code> and <code>azimuthFinish</code>.
+ *     emitted from the portion of the shape that lies between <code>azimuthStart<code> and <code>azimuthFinish</code>.
- *     Only used if <code>shapeType</code> is <code>ellipsoid</code>.
+ *     Only used if <code>shapeType</code> is <code>ellipsoid</code>, <code>sphere</code>, or <code>circle</code>.
  * @property {number} azimuthFinish=Math.PI - The angle in radians from the entity's local x-axis about the entity's local
  *     z-axis at which particles stop being emitted; range <code>-Math.PI</code> &ndash; <code>Math.PI</code>. Particles are
- *     emitted from the portion of the ellipsoid that lies between <code>azimuthStart<code> and <code>azimuthFinish</code>.
+ *     emitted from the portion of the shape that lies between <code>azimuthStart<code> and <code>azimuthFinish</code>.
- *     Only used if <code>shapeType</code> is <code>ellipsoid</code>.
+ *     Only used if <code>shapeType</code> is <code>ellipsoid</code>, <code>sphere</code>, or <code>circle</code>..
  *
  * @property {string} textures="" - The URL of a JPG or PNG image file to display for each particle. If you want transparency,
  *     use PNG format.

libraries/entities/src/LineEntityItem.h

@@ -49,8 +49,6 @@ class LineEntityItem : public EntityItem {
 
     QVector<glm::vec3> getLinePoints() const;
 
-    virtual ShapeType getShapeType() const override { return SHAPE_TYPE_NONE; }
-
     // never have a ray intersection pick a LineEntityItem.
     virtual bool supportsDetailedIntersection() const override { return true; }
     virtual bool findDetailedRayIntersection(const glm::vec3& origin, const glm::vec3& direction,

libraries/entities/src/ModelEntityItem.h

@@ -175,7 +175,7 @@ protected:
 
     QString _textures;
 
-    ShapeType _shapeType = SHAPE_TYPE_NONE;
+    ShapeType _shapeType { SHAPE_TYPE_NONE } ;
 
 private:
     uint64_t _lastAnimated{ 0 };

libraries/entities/src/ShapeEntityItem.h

@@ -112,7 +112,7 @@ protected:
     //! This is SHAPE_TYPE_ELLIPSOID rather than SHAPE_TYPE_NONE to maintain
     //! prior functionality where new or unsupported shapes are treated as
     //! ellipsoids.
-    ShapeType _collisionShapeType{ ShapeType::SHAPE_TYPE_ELLIPSOID };
+    ShapeType _collisionShapeType { ShapeType::SHAPE_TYPE_ELLIPSOID };
 };
 
 #endif // hifi_ShapeEntityItem_h

libraries/entities/src/ZoneEntityItem.cpp

@@ -352,7 +352,7 @@ bool ZoneEntityItem::contains(const glm::vec3& point) const {
 
             Extents meshExtents = hfmModel.getMeshExtents();
             glm::vec3 meshExtentsDiagonal = meshExtents.maximum - meshExtents.minimum;
-            glm::vec3 offset = -meshExtents.minimum- (meshExtentsDiagonal * getRegistrationPoint());
+            glm::vec3 offset = -meshExtents.minimum - (meshExtentsDiagonal * getRegistrationPoint());
             glm::vec3 scale(getScaledDimensions() / meshExtentsDiagonal);
 
             glm::mat4 hfmToEntityMatrix = glm::scale(scale) * glm::translate(offset);

libraries/entities/src/ZoneEntityItem.h

@@ -133,7 +133,7 @@ protected:
     KeyLightPropertyGroup _keyLightProperties;
     AmbientLightPropertyGroup _ambientLightProperties;
 
-    ShapeType _shapeType = DEFAULT_SHAPE_TYPE;
+    ShapeType _shapeType { DEFAULT_SHAPE_TYPE };
     QString _compoundShapeURL;
 
     // The following 3 values are the defaults for zone creation

libraries/shared/src/GeometryUtil.cpp

@@ -358,6 +358,12 @@ glm::vec3 Triangle::getNormal() const {
     return glm::normalize(glm::cross(edge1, edge2));
 }
 
+float Triangle::getArea() const {
+    glm::vec3 edge1 = v1 - v0;
+    glm::vec3 edge2 = v2 - v0;
+    return 0.5f * glm::length(glm::cross(edge1, edge2));
+}
+
 Triangle Triangle::operator*(const glm::mat4& transform) const {
     return {
         glm::vec3(transform * glm::vec4(v0, 1.0f)),

libraries/shared/src/GeometryUtil.h

@@ -125,6 +125,7 @@ public:
     glm::vec3 v1;
     glm::vec3 v2;
     glm::vec3 getNormal() const;
+    float getArea() const;
     Triangle operator*(const glm::mat4& transform) const;
 };
 

scripts/system/assets/data/createAppTooltips.json

@@ -227,6 +227,14 @@
     "speedSpread": {
         "tooltip": "The spread in speeds at which particles are emitted at, resulting in a variety of speeds."
     },
+    "particleShapeType": {
+        "tooltip": "The shape of the surface from which to emit particles.",
+        "jsPropertyName": "shapeType"
+    },
+    "particleCompoundShapeURL": {
+        "tooltip": "The model file to use for the particle emitter if Shape Type is \"Use Compound Shape URL\".",
+        "jsPropertyName": "compoundShapeURL"
+    },
     "emitDimensions": {
         "tooltip": "The outer limit radius in dimensions that the particles can be emitted from."
     },

scripts/system/html/js/entityProperties.js

@@ -807,6 +807,21 @@ const GROUPS = [
                 decimals: 2,
                 propertyID: "speedSpread",
             },
+            {
+                label: "Shape Type",
+                type: "dropdown",
+                options: { "box": "Box", "ellipsoid": "Ellipsoid", 
+                           "cylinder-y": "Cylinder", "circle": "Circle", "plane": "Plane",
+                           "compound": "Use Compound Shape URL" },
+                propertyID: "particleShapeType",
+                propertyName: "shapeType",
+            },
+            {
+                label: "Compound Shape URL",
+                type: "string",
+                propertyID: "particleCompoundShapeURL",
+                propertyName: "compoundShapeURL",
+            },
             {
                 label: "Emit Dimensions",
                 type: "vec3",