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use air bfs traversal instead of shell iteration for better result
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@douira
douira committed Nov 25, 2024
1 parent ea43041 commit b7a5501
Showing 1 changed file with 72 additions and 51 deletions.
123 changes: 72 additions & 51 deletions ...c/main/java/net/caffeinemc/mods/sodium/client/render/chunk/occlusion/OcclusionCuller.java
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Original file line number Diff line number Diff line change
@@ -1,6 +1,8 @@
package net.caffeinemc.mods.sodium.client.render.chunk.occlusion;

import it.unimi.dsi.fastutil.longs.Long2ReferenceMap;
import it.unimi.dsi.fastutil.longs.LongArrayFIFOQueue;
import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
import net.caffeinemc.mods.sodium.client.render.chunk.RenderSection;
import net.caffeinemc.mods.sodium.client.render.viewport.CameraTransform;
import net.caffeinemc.mods.sodium.client.render.viewport.Viewport;
Expand All @@ -17,6 +19,8 @@ public class OcclusionCuller {
private final Level level;

private final DoubleBufferedQueue<RenderSection> queue = new DoubleBufferedQueue<>();
private LongArrayFIFOQueue initQueue;
private LongOpenHashSet initVisited;

public OcclusionCuller(Long2ReferenceMap<RenderSection> sections, Level level) {
this.sections = sections;
Expand Down Expand Up @@ -180,10 +184,14 @@ private static int getOutwardDirections(SectionPos origin, RenderSection section
}

private static boolean isWithinRenderDistance(CameraTransform camera, RenderSection section, float maxDistance) {
return isWithinRenderDistance(camera, section.getOriginX(), section.getOriginY(), section.getOriginZ(), maxDistance);
}

private static boolean isWithinRenderDistance(CameraTransform camera, int originX, int originY, int originZ, float maxDistance) {
// origin point of the chunk's bounding box (in view space)
int ox = section.getOriginX() - camera.intX;
int oy = section.getOriginY() - camera.intY;
int oz = section.getOriginZ() - camera.intZ;
int ox = originX - camera.intX;
int oy = originY - camera.intY;
int oz = originZ - camera.intZ;

// coordinates of the point to compare (in view space)
// this is the closest point within the bounding box to the center (0, 0, 0)
Expand Down Expand Up @@ -237,7 +245,7 @@ private void init(Visitor visitor,
if (originSection != null) {
this.initAtExistingSection(visitor, queue, originSection, useOcclusionCulling, frame);
} else {
this.initAtNonExistingSection(visitor, queue, viewport, useOcclusionCulling, searchDistance, frame);
this.initAtNonExistingSection(queue, viewport, searchDistance, frame);
}
}
}
Expand All @@ -262,64 +270,77 @@ private void initAtExistingSection(Visitor visitor, WriteQueue<RenderSection> qu
visitNeighbors(queue, section, outgoing, frame);
}

private void initAtNonExistingSection(Visitor visitor, WriteQueue<RenderSection> queue, Viewport viewport, boolean useOcclusionCulling, float searchDistance, int frame) {
private void initAtNonExistingSection(WriteQueue<RenderSection> queue, Viewport viewport, float searchDistance, int frame) {
var transform = viewport.getTransform();

var origin = viewport.getChunkCoord();
if (this.initQueue == null) {
this.initQueue = new LongArrayFIFOQueue(200);
} else {
this.initQueue.clear();
}
if (this.initVisited == null) {
this.initVisited = new LongOpenHashSet(200);
} else {
this.initVisited.clear();
}

var originPos = origin.asLong();
this.initQueue.enqueue(originPos);
this.initVisited.add(originPos);

var minY = this.level.getMinSectionY();
var maxY = this.level.getMaxSectionY();
var originX = origin.getX();
var originY = origin.getY();
var originZ = origin.getZ();

// iterate shells until one is found with a loaded and visible section
var foundAny = false;
var radius = 1;
while (!foundAny) {
// iterate a shell around the origin
var bigStep = radius * 2;
for (var dy = -radius; dy <= radius; dy++) {
var y = originY + dy;
// skip layers outside the world's y range
if (y < minY || y > maxY) {
continue;
}
while (!this.initQueue.isEmpty()) {
var current = this.initQueue.dequeueLong();

// iterate only the perimeter with the current radius
var notYFace = !(dy == -radius || dy == radius);
for (var dx = -radius; dx <= radius; dx++) {
var zStep = notYFace && (dx == -radius || dx == radius) ? bigStep : 1;
for (var dz = -radius; dz <= radius; dz += zStep) {
var x = originX + dx;
var z = originZ + dz;

// visit loaded visible sections and queue their neighbors
var section = this.getRenderSection(x, y, z);
if (section != null && isSectionVisible(section, viewport, searchDistance)) {
foundAny = true;

// use all directions as incoming, using just some yields a broken result
var incoming = GraphDirectionSet.ALL;
section.setIncomingDirections(incoming);
section.setLastVisibleFrame(frame);

visitor.visit(section);

// reduce set of neighbors to visit based on visibility connections
int connections = getOutwardDirections(origin, section);
if (useOcclusionCulling) {
connections &= VisibilityEncoding.getConnections(section.getVisibilityData(), incoming);
}

visitNeighbors(queue, section, connections, frame);
}
}
}
var x = SectionPos.x(current);
var y = SectionPos.y(current);
var z = SectionPos.z(current);

// visit neighbors and add them to the init queue and/or the main graph traversal queue
if (x <= originX) {
visitEmptyNeighbor(queue, frame, transform, searchDistance, x - 1, y, z, GraphDirection.WEST);
}
if (x >= originX) {
visitEmptyNeighbor(queue, frame, transform, searchDistance, x + 1, y, z, GraphDirection.EAST);
}
if (y <= originY && y > minY) {
visitEmptyNeighbor(queue, frame, transform, searchDistance, x, y - 1, z, GraphDirection.DOWN);
}
if (y >= originY && y < maxY) {
visitEmptyNeighbor(queue, frame, transform, searchDistance, x, y + 1, z, GraphDirection.UP);
}
if (z <= originZ) {
visitEmptyNeighbor(queue, frame, transform, searchDistance, x, y, z - 1, GraphDirection.NORTH);
}
if (z >= originZ) {
visitEmptyNeighbor(queue, frame, transform, searchDistance, x, y, z + 1, GraphDirection.SOUTH);
}
}
}

private void visitEmptyNeighbor(WriteQueue<RenderSection> queue, int frame, CameraTransform transform, float searchDistance, int x, int y, int z, int incoming) {
if (!isWithinRenderDistance(transform, x << 4, y << 4, z << 4, searchDistance)) {
return;
}

var pos = SectionPos.asLong(x, y, z);
var section = this.sections.get(pos);

radius++;
// sections that exist get queued
if (section != null) {
visitNode(queue, section, incoming, frame);
}

// don't exceed the search distance with the init search
if (radius << 4 > searchDistance) {
break;
// sections that don't exist or are empty are further traversed in the init process
if (section == null || section.getFlags() == 0) {
if (this.initVisited.add(pos)) {
this.initQueue.enqueue(pos);
}
}
}
Expand Down

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