Improved vegetation rendering

- Added early check on terrain height range during iteration
- Added test render of vegetation model
- Tweaked basic tree model

src/basics/Disk.cpp

@@ -2,10 +2,6 @@
 
 #include "PackStream.h"
 
-Disk::Disk()
-{
-}
-
 Disk::Disk(const Vector3 &point, const Vector3 &normal, double radius):
     InfinitePlane(point, normal), radius(radius)
 {

src/basics/Disk.h

@@ -14,7 +14,7 @@ namespace basics {
 class BASICSSHARED_EXPORT Disk: public InfinitePlane
 {
 public:
-    Disk();
+    Disk() = default;
     Disk(const Vector3 &point, const Vector3 &normal, double radius);
 
     inline double getRadius() const {return radius;}

src/basics/SpaceSegment.cpp

@@ -2,6 +2,7 @@
 
 #include <climits>
 #include "SpaceGridIterator.h"
+using namespace std;
 
 SpaceSegment::SpaceSegment(const Vector3& start, const Vector3& end):
     start(start), end(end)
@@ -58,6 +59,44 @@ bool SpaceSegment::intersectYInterval(double ymin, double ymax)
     return true;
 }
 
+bool SpaceSegment::intersectBoundingBox(const SpaceSegment &bbox) const
+{
+    Vector3 dir = getDirection();
+    // r.dir is unit direction vector of ray
+    double dfx = 1.0 / dir.x;
+    double dfy = 1.0 / dir.y;
+    double dfz = 1.0 / dir.z;
+    // lb is the corner of AABB with minimal coordinates - left bottom, rt is maximal corner
+    // r.org is origin of ray
+    double t1 = (bbox.start.x - start.x) * dfx;
+    double t2 = (bbox.end.x - start.x) * dfx;
+    double t3 = (bbox.start.y - start.y) * dfy;
+    double t4 = (bbox.end.y - start.y) * dfy;
+    double t5 = (bbox.start.z - start.z) * dfz;
+    double t6 = (bbox.end.z - start.z) * dfz;
+
+    double tmin = max(max(min(t1, t2), min(t3, t4)), min(t5, t6));
+    double tmax = min(min(max(t1, t2), max(t3, t4)), max(t5, t6));
+
+    // if tmax < 0, ray (line) is intersecting AABB, but whole AABB is behing us
+    double t;
+    if (tmax < 0.0)
+    {
+        t = tmax;
+        return false;
+    }
+
+    // if tmin > tmax, ray doesn't intersect AABB
+    if (tmin > tmax)
+    {
+        t = tmax;
+        return false;
+    }
+
+    t = tmin;
+    return true;
+}
+
 SpaceSegment SpaceSegment::projectedOnXPlane(double x) const
 {
     return SpaceSegment(Vector3(x, start.y, start.z), Vector3(x, end.y, end.z));

src/basics/SpaceSegment.h

@@ -33,6 +33,11 @@ public:
      */
     bool intersectYInterval(double ymin, double ymax);
 
+    /**
+     * Return true if the segment intersects a bounding box, represented by another segment (crossing diagonal).
+     */
+    bool intersectBoundingBox(const SpaceSegment &bbox) const;
+
     /**
      * Return a version of this segment, projected on a X plane.
      */

src/definition/VegetationModelDefinition.cpp

@@ -119,7 +119,6 @@ static void addBranchRecurse(std::vector<CappedCylinder> &branches, const Vector
     if (length > 0.1)
     {
         int split_count = 3;
-        Vector3 new_base = base.add(direction.scale(length));
         Matrix4 pivot1 = Matrix4::newRotateAxis(randomizeValue(1.0 - 0.6 * length, 0.9, 1.1), VECTOR_EAST);
         Vector3 new_direction = pivot1.multPoint(direction);
         for (int i = 0; i < split_count; i++)
@@ -127,7 +126,8 @@ static void addBranchRecurse(std::vector<CappedCylinder> &branches, const Vector
             Matrix4 pivot2 = Matrix4::newRotateAxis(randomizeValue(M_PI * 2.0 / (double)split_count, 0.9, 1.1), direction);
             new_direction = pivot2.multPoint(new_direction);
 
-            addBranchRecurse(branches, new_base, new_direction, randomizeValue(radius, 0.65, 0.75), randomizeValue(length, 0.55, 0.65));
+            Vector3 new_base = base.add(direction.scale(randomizeValue(length, 0.4, 1.0)));
+            addBranchRecurse(branches, new_base, new_direction, randomizeValue(radius, 0.45, 0.6), randomizeValue(length, 0.55, 0.85));
         }
     }
 }
@@ -140,7 +140,7 @@ void VegetationModelDefinition::randomize()
     foliage_items.clear();
 
     // Add trunk and branches
-    addBranchRecurse(solid_volumes, VECTOR_ZERO, VECTOR_UP, 0.05, 0.5);
+    addBranchRecurse(solid_volumes, VECTOR_ZERO, VECTOR_UP, 0.04, 0.5);
 
     // Add foliage groups
     for (const auto &branch: solid_volumes)
@@ -150,7 +150,7 @@ void VegetationModelDefinition::randomize()
         {
             double radius = length * 0.5;
             Vector3 center = branch.getAxis().getOrigin().add(branch.getAxis().getDirection().scale(radius));
-            foliage_groups.push_back(Sphere(center, radius * 5.0));
+            foliage_groups.push_back(Sphere(center, radius * 3.0));
         }
     }
 
@@ -159,7 +159,7 @@ void VegetationModelDefinition::randomize()
     {
         double radius = 0.15;
         Vector3 dir = Vector3::randomInSphere(1.0 - radius);
-        Vector3 normal = dir.add(Vector3::randomInSphere(0.4)).add(Vector3(0.0, 0.6, 0.0)).normalize();
+        Vector3 normal = dir.add(Vector3::randomInSphere(0.4)).add(Vector3(0.0, 0.3, 0.0)).normalize();
         Disk leaf(dir, normal, randomizeValue(radius, 0.8, 1.0));
         foliage_items.push_back(leaf);
     }

src/interface/commandline/tests.cpp

@@ -17,6 +17,12 @@
 #include "LightFilter.h"
 #include "GodRaysSampler.h"
 #include "Rasterizer.h"
+#include "SpaceSegment.h"
+#include "OverlayRasterizer.h"
+#include "VegetationModelDefinition.h"
+#include "VegetationInstance.h"
+#include "VegetationRenderer.h"
+#include "RayCastingResult.h"
 
 #include <sstream>
 
@@ -251,6 +257,50 @@ static void testSunNearHorizon()
     }
 }
 
+static void testVegetationModels()
+{
+    class TestRasterizer: public OverlayRasterizer
+    {
+    public:
+        TestRasterizer(SoftwareCanvasRenderer *renderer, const VegetationModelDefinition &model):
+            OverlayRasterizer(renderer, renderer->getProgressHelper()),
+            instance(model, VECTOR_ZERO),
+            vegetation(renderer->getVegetationRenderer())
+        {
+        }
+
+        virtual Color processPixel(int, int, double relx, double rely) const override
+        {
+            relx *= 0.75;
+            rely *= 0.75;
+            SpaceSegment segment(Vector3(relx, rely + 0.5, -5.0), Vector3(relx, rely + 0.5, 5.0));
+            RayCastingResult result = vegetation->renderInstance(segment, instance, false, true);
+            return result.hit ? result.hit_color : Color(0.6, 0.7, 0.9);
+        }
+
+        VegetationInstance instance;
+        VegetationRenderer *vegetation;
+    };
+
+    Scenery scenery;
+    scenery.autoPreset(1);
+    scenery.getClouds()->clear();
+    scenery.getTerrain()->propWaterHeight()->setValue(1.0);
+    scenery.getCamera()->setTarget(VECTOR_ZERO);
+    scenery.getCamera()->setLocation(Vector3(0.0, 0.0, -5.0));
+    int width = 800;
+    int height = 800;
+
+    SoftwareCanvasRenderer renderer(&scenery);
+    renderer.setSize(width, height);
+    renderer.setQuality(0.5);
+
+    VegetationModelDefinition model(NULL);
+    renderer.setSoloRasterizer(new TestRasterizer(&renderer, model));
+
+    startTestRender(&renderer, "vegetation_model_basic");
+}
+
 void runTestSuite()
 {
     testGroundShadowQuality();
@@ -260,4 +310,5 @@ void runTestSuite()
     testNearFrustum();
     testCloudsNearGround();
     testSunNearHorizon();
+    testVegetationModels();
 }

src/render/software/OverlayRasterizer.cpp

@@ -0,0 +1,52 @@
+#include "OverlayRasterizer.h"
+
+#include "Color.h"
+#include "SoftwareRenderer.h"
+#include "CameraDefinition.h"
+#include "CanvasFragment.h"
+
+OverlayRasterizer::OverlayRasterizer(SoftwareRenderer *renderer, RenderProgress *progress):
+    Rasterizer(renderer, progress, 0, COLOR_WHITE)
+{
+}
+
+int OverlayRasterizer::prepareRasterization()
+{
+    return 1;
+}
+
+void OverlayRasterizer::rasterizeToCanvas(CanvasPortion *canvas)
+{
+    double width = (double)renderer->render_camera->getWidth();
+    double height = (double)renderer->render_camera->getHeight();
+    Vector3 topleft = renderer->unprojectPoint(Vector3(height, 0.0, 1.0));
+    Vector3 bottomleft = renderer->unprojectPoint(Vector3(0.0, 0.0, 1.0));
+    Vector3 topright = renderer->unprojectPoint(Vector3(height, width, 1.0));
+    Vector3 bottomright = renderer->unprojectPoint(Vector3(0.0, width, 1.0));
+
+    pushQuad(canvas, topleft, bottomleft, bottomright, topright);
+}
+
+Color OverlayRasterizer::shadeFragment(const CanvasFragment &fragment, const CanvasFragment *) const
+{
+    double width = (double)renderer->render_camera->getWidth() - 1.0;
+    double height = (double)renderer->render_camera->getHeight() - 1.0;
+    double relx;
+    double rely;
+    double x = floor(fragment.getPixel().x);
+    double y = floor(fragment.getPixel().y);
+
+    if (width > height)
+    {
+        relx = 2.0 * ((x - (width - height) * 0.5) / height - 0.5);
+        rely = 2.0 * (y / height - 0.5);
+    }
+    else
+    {
+        relx = 2.0 * (x / height - 0.5);
+        rely = 2.0 * ((y - (height - width) * 0.5) / height - 0.5);
+    }
+
+    return processPixel((int)x, (int)y, relx, rely);
+}
+

src/render/software/OverlayRasterizer.h

@@ -0,0 +1,35 @@
+#ifndef OVERLAYRASTERIZER_H
+#define OVERLAYRASTERIZER_H
+
+#include "software_global.h"
+
+#include "Rasterizer.h"
+
+namespace paysages {
+namespace software {
+
+/**
+ * Base class for overlay rasterizer.
+ *
+ * It's a rasterizer that puts a single quad in front of camera, in order to apply a shader on each pixel.
+ */
+class SOFTWARESHARED_EXPORT OverlayRasterizer: public Rasterizer
+{
+public:
+    OverlayRasterizer(SoftwareRenderer *renderer, RenderProgress *progress);
+
+    /**
+     * Abstract method to implement to shade each pixel.
+     */
+    virtual Color processPixel(int x, int y, double relx, double rely) const = 0;
+
+private:
+    virtual int prepareRasterization();
+    virtual void rasterizeToCanvas(CanvasPortion *canvas);
+    virtual Color shadeFragment(const CanvasFragment &fragment, const CanvasFragment *previous) const;
+};
+
+}
+}
+
+#endif // OVERLAYRASTERIZER_H

src/render/software/TerrainRenderer.cpp

@@ -220,3 +220,18 @@ bool TerrainRenderer::applyLightFilter(LightComponent &light, const Vector3 &at)
         return true;
     }
 }
+
+void TerrainRenderer::estimateMinMaxHeight(double x1, double z1, double x2, double z2, double *ymin, double *ymax)
+{
+    double y1 = getHeight(x1, z1, true);
+    double y2 = getHeight(x2, z2, true);
+
+    // TODO Add quality factor
+    // TODO Use all 4 corners
+    // TODO Apply max slope
+    // TODO Estimate displacement
+
+    std::pair<double, double>minmax = std::minmax(y1, y2);
+    *ymin = minmax.first;
+    *ymax = minmax.second;
+}

src/render/software/TerrainRenderer.h

@@ -34,6 +34,11 @@ public:
     virtual Color getFinalColor(const Vector3 &location, double precision);
     virtual bool applyLightFilter(LightComponent &light, const Vector3 &at) override;
 
+    /**
+     * Estimate a probable range of altitudes, given a rectangle area.
+     */
+    void estimateMinMaxHeight(double x1, double z1, double x2, double z2, double *ymin, double *ymax);
+
 private:
     SoftwareRenderer *parent;
     TerrainRayWalker *walker_ray;

src/render/software/VegetationModelRenderer.cpp

@@ -113,7 +113,6 @@ VegetationResult VegetationModelRenderer::getResult(const SpaceSegment &segment,
         material.shininess = 3.0;
         material.hardness = 0.3;
         material.validate();
-        // FIXME Can't use reference to temporary material
         return VegetationResult(location, normal, material);
     }
     else

src/render/software/VegetationRenderer.cpp

@@ -21,8 +21,8 @@
 class VegetationGridIterator: public SpaceGridIterator
 {
 public:
-    VegetationGridIterator(const SpaceSegment &segment, VegetationRenderer *renderer, VegetationLayerDefinition *layer, bool only_hit):
-        segment(segment), renderer(renderer), layer(layer), only_hit(only_hit)
+    VegetationGridIterator(const SpaceSegment &segment, VegetationRenderer *renderer, bool only_hit):
+        segment(segment), renderer(renderer), only_hit(only_hit)
     {
     }
 
@@ -30,24 +30,12 @@ public:
 
     virtual bool onCell(int x, int, int z) override
     {
-        std::vector<VegetationInstance> instances;
-
-        layer->getPresence()->collectInstances(&instances, *layer->getModel(), x - 0.5, z - 0.5, x + 0.5, z + 0.5);
-
-        for (auto &instance: instances)
-        {
-            result = renderer->renderInstance(segment, instance, only_hit);
-            if (result.hit)
-            {
-                return false;
-            }
-        }
-        return true;
+        result = renderer->getBoundResult(segment, (double)x, (double)z, only_hit);
+        return not result.hit;
     }
 private:
     const SpaceSegment &segment;
     VegetationRenderer *renderer;
-    VegetationLayerDefinition *layer;
     RayCastingResult result;
     bool only_hit;
 };
@@ -97,17 +85,11 @@ RayCastingResult VegetationRenderer::getResult(const SpaceSegment &segment, bool
 {
     if (enabled)
     {
-        VegetationDefinition *vegetation = parent->getScenery()->getVegetation();
-        int n = vegetation->count();
-        // TODO Don't stop at first layer, find the nearest hit
-        for (int i = 0; i < n; i++)
+        // Find instances potentially crossing the segment
+        VegetationGridIterator it(segment, this, only_hit);
+        if (not segment.projectedOnYPlane().iterateOnGrid(it))
         {
-            // Find instances potentially crossing the segment
-            VegetationGridIterator it(segment, this, vegetation->getVegetationLayer(i), only_hit);
-            if (not segment.projectedOnYPlane().iterateOnGrid(it))
-            {
-                return it.getResult();
-            }
+            return it.getResult();
         }
         return RayCastingResult();
     }
@@ -117,6 +99,42 @@ RayCastingResult VegetationRenderer::getResult(const SpaceSegment &segment, bool
     }
 }
 
+RayCastingResult VegetationRenderer::getBoundResult(const SpaceSegment &segment, double x, double z, bool only_hit, double xsize, double zsize)
+{
+    // Early check if we may cross any vegetation
+    double ymin, ymax;
+    double vegetation_max_height = 0.0;  // TODO
+    parent->getTerrainRenderer()->estimateMinMaxHeight(x, z, x + xsize, z + zsize, &ymin, &ymax);
+    ymax += vegetation_max_height;
+    SpaceSegment bbox(Vector3(x, ymin, z), Vector3(x + xsize, ymax, z + zsize));
+    if (not segment.intersectBoundingBox(bbox)) {
+        return RayCastingResult();
+    }
+
+    // Iterate all layers and instances
+    VegetationDefinition *vegetation = parent->getScenery()->getVegetation();
+    int n = vegetation->count();
+    for (int i = 0; i < n; i++)
+    {
+        VegetationLayerDefinition *layer = vegetation->getVegetationLayer(i);
+
+        std::vector<VegetationInstance> instances;
+        layer->getPresence()->collectInstances(&instances, *layer->getModel(), x, z, x + xsize, z + zsize);
+
+        for (auto &instance: instances)
+        {
+            RayCastingResult result = renderInstance(segment, instance, only_hit);
+            if (result.hit)
+            {
+                // TODO Don't stop at first hit, find the nearest one
+                return result;
+            }
+        }
+    }
+
+    return RayCastingResult();
+}
+
 bool VegetationRenderer::applyLightFilter(LightComponent &light, const Vector3 &at)
 {
     if (enabled)

src/render/software/VegetationRenderer.h

@@ -34,6 +34,11 @@ public:
      */
     RayCastingResult getResult(const SpaceSegment &segment, bool only_hit=false);
 
+    /**
+     * Perform ray casting on a squared region.
+     */
+    RayCastingResult getBoundResult(const SpaceSegment &segment, double x, double z, bool only_hit=false, double xsize=1.0, double zsize=1.0);
+
     virtual bool applyLightFilter(LightComponent &light, const Vector3 &at) override;
 
 private:

src/render/software/software_global.h

@@ -36,6 +36,7 @@ namespace software {
     class WaterRenderer;
 
     class Rasterizer;
+    class OverlayRasterizer;
     class SkyRasterizer;
     class TerrainRasterizer;
 

src/tests/OverlayRasterizer_Test.cpp

@@ -0,0 +1,65 @@
+#include "BaseTestCase.h"
+#include "OverlayRasterizer.h"
+
+#include <vector>
+#include "Scenery.h"
+#include "SoftwareCanvasRenderer.h"
+#include "Color.h"
+
+typedef struct {
+    int x;
+    int y;
+    double relx;
+    double rely;
+} PixelCall;
+
+std::vector<PixelCall> calls;
+
+class MockOverlayRasterizer: public OverlayRasterizer
+{
+public:
+    MockOverlayRasterizer(SoftwareCanvasRenderer *renderer):
+        OverlayRasterizer(renderer, renderer->getProgressHelper())
+    {
+    }
+
+    virtual Color processPixel(int x, int y, double relx, double rely) const override
+    {
+        PixelCall call = {x, y, relx, rely};
+        calls.push_back(call);
+        return COLOR_BLUE;
+    }
+};
+
+void checkCall(const PixelCall &call, int x, int y, double relx, double rely)
+{
+    EXPECT_EQ(x, call.x);
+    EXPECT_EQ(y, call.y);
+    EXPECT_DOUBLE_EQ(relx, call.relx);
+    EXPECT_DOUBLE_EQ(rely, call.rely);
+}
+
+TEST(OverlayRasterizer, pixelProcessing)
+{
+    calls.clear();
+
+    Scenery scenery;
+    SoftwareCanvasRenderer renderer(&scenery);
+    renderer.setSize(4, 3);
+    renderer.setSoloRasterizer(new MockOverlayRasterizer(&renderer));
+    renderer.render();
+
+    ASSERT_EQ(12, (int)calls.size());
+    checkCall(calls[0], 0, 0, -1.5, -1.0);
+    checkCall(calls[1], 0, 2, -1.5, 1.0);
+    checkCall(calls[2], 2, 0, 0.5, -1.0);
+    checkCall(calls[3], 2, 2, 0.5, 1.0);
+    checkCall(calls[4], 0, 1, -1.5, 0.0);
+    checkCall(calls[5], 1, 0, -0.5, -1.0);
+    checkCall(calls[6], 1, 1, -0.5, 0.0);
+    checkCall(calls[7], 1, 2, -0.5, 1.0);
+    checkCall(calls[8], 2, 1, 0.5, 0.0);
+    checkCall(calls[9], 3, 0, 1.5, -1.0);
+    checkCall(calls[10], 3, 1, 1.5, 0.0);
+    checkCall(calls[11], 3, 2, 1.5, 1.0);
+}

src/tests/SpaceSegment_Test.cpp

@@ -59,3 +59,18 @@ TEST(SpaceSegment, iterateOnGrid_Negative)
     ASSERT_EQ(1, (int)it.locations.size());
     EXPECT_VECTOR3_COORDS(it.locations[0], -9.0, -9.0, -9.0);
 }
+
+TEST(SpaceSegment, intersectBoundingBox)
+{
+    SpaceSegment bbox(Vector3(-1.0, -1.0, -1.0), Vector3(1.0, 4.0, 1.0));
+
+    EXPECT_TRUE(SpaceSegment(Vector3(0.0, 0.0, 0.0), Vector3(1.0, 1.0, 1.0)).intersectBoundingBox(bbox));
+
+    EXPECT_TRUE(SpaceSegment(Vector3(-5.0, 0.0, 0.0), Vector3(5.0, 0.0, 0.0)).intersectBoundingBox(bbox));
+    EXPECT_FALSE(SpaceSegment(Vector3(-5.0, -2.0, 0.0), Vector3(5.0, -2.0, 0.0)).intersectBoundingBox(bbox));
+
+    EXPECT_TRUE(SpaceSegment(Vector3(-5.0, 0.0, -5.0), Vector3(5.0, 0.0, 5.0)).intersectBoundingBox(bbox));
+    EXPECT_FALSE(SpaceSegment(Vector3(-5.0, -2.0, 0.0), Vector3(5.0, -2.0, 5.0)).intersectBoundingBox(bbox));
+
+    EXPECT_FALSE(SpaceSegment(Vector3(-10.0, 0.0, 0.0), Vector3(10.0, -6.0, 0.0)).intersectBoundingBox(bbox));
+}