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stupidsimcpp/util/grid/grid3.hpp
2025-11-11 10:48:52 -05:00

428 lines
16 KiB
C++

#ifndef GRID3_HPP
#define GRID3_HPP
#include "vec3.hpp"
#include "vec4.hpp"
#include <vector>
#include <unordered_map>
#include <string>
#include <algorithm>
#include <map>
#include <unordered_set>
class Grid3 {
private:
// size_t is index
// Vec3 is x,y,z position of the sparse voxel
std::multimap<size_t, Vec3> positions;
// Vec4 is rgba color at the position
std::multimap<size_t, Vec4> colors;
// size is a floating size to assign to a voxel to allow larger or smaller assignments
std::multimap<size_t, float> sizes;
size_t next_id;
std::unordered_map<size_t, std::tuple<int, int, int>> cellIndices; // object ID -> grid cell
std::unordered_map<std::tuple<int, int, int>, std::unordered_set<size_t>> spatialGrid; // cell -> object IDs
float cellSize;
public:
Grid3() : next_id(0), cellSize(1.0f) {}
Grid3(float cellSize) : next_id(0), cellSize(cellSize) {}
size_t addObject(const Vec3& position, const Vec4& color, float size = 1.0f) {
size_t id = next_id++;
positions.insert({id, position});
colors.insert({id, color});
sizes.insert({id, size});
auto cell = worldToGrid(position);
spatialGrid[cell].insert(id);
cellIndices[id] = cell;
return id;
}
// Gets
Vec3 getPosition(size_t id) const {
auto it = positions.find(id);
if (it != positions.end()) return it->second;
return Vec3();
}
Vec4 getColor(size_t id) const {
auto it = colors.find(id);
if (it != colors.end()) return it->second;
return Vec4();
}
float getSize(size_t id) const {
auto it = sizes.find(id);
if (it != sizes.end()) return it->second;
return 1.0f;
}
// Sets
void setPosition(size_t id, const Vec3& position) {
if (!hasObject(id)) return;
Vec3 oldPos = getPosition(id);
positions.erase(id);
positions.insert({id, position});
updateSpatialIndex(id, oldPos, position);
}
void setColor(size_t id, const Vec4& color) {
colors.erase(id);
colors.insert({id, color});
}
void setSize(size_t id, float size) {
sizes.erase(id);
sizes.insert({id, size});
}
// Batch add/remove operations
void addObjects(const std::vector<std::tuple<Vec3, Vec4, float>>& objects) {
for (const auto& obj : objects) {
addObject(std::get<0>(obj), std::get<1>(obj), std::get<2>(obj));
}
}
void removeObjects(const std::vector<size_t>& ids) {
for (size_t id : ids) {
removeObject(id);
}
}
// Batch position updates
void updatePositions(const std::unordered_map<size_t, Vec3>& newPositions) {
// Bulk update spatial grid - collect all changes first
std::vector<std::tuple<size_t, Vec3, Vec3>> spatialUpdates;
for (const auto& pair : newPositions) {
if (hasObject(pair.first)) {
Vec3 oldPos = getPosition(pair.first);
positions.erase(pair.first);
positions.insert({pair.first, pair.second});
spatialUpdates.emplace_back(pair.first, oldPos, pair.second);
}
}
// Apply all spatial updates at once
for (const auto& update : spatialUpdates) {
updateSpatialIndex(std::get<0>(update), std::get<1>(update), std::get<2>(update));
}
}
// Other
bool hasObject(size_t id) const {
return positions.find(id) != positions.end();
}
void removeObject(size_t id) {
// Remove from spatial grid first
auto cellIt = cellIndices.find(id);
if (cellIt != cellIndices.end()) {
auto& cellObjects = spatialGrid[cellIt->second];
cellObjects.erase(id);
if (cellObjects.empty()) {
spatialGrid.erase(cellIt->second);
}
cellIndices.erase(id);
}
// Remove from data maps
positions.erase(id);
colors.erase(id);
sizes.erase(id);
}
std::vector<size_t> getIndicesAt(float x, float y, float z, float radius = 0.0f) const {
return getIndicesAt(Vec3(x, y, z), radius);
}
std::vector<size_t> getIndicesAt(const Vec3& position, float radius = 0.0f) const {
std::vector<size_t> result;
if (radius <= 0.0f) {
// Exact position match
for (const auto& pair : positions) {
if (pair.second == position) {
result.push_back(pair.first);
}
}
} else {
// Radius-based search
float radius_sq = radius * radius;
for (const auto& pair : positions) {
float dx = pair.second.x - position.x;
float dy = pair.second.y - position.y;
float dz = pair.second.z - position.z;
if (dx * dx + dy * dy + dz * dz <= radius_sq) {
result.push_back(pair.first);
}
}
}
return result;
}
void getBoundingBox(Vec3& minCorner, Vec3& maxCorner) const {
if (positions.empty()) {
minCorner = Vec3(0.0f, 0.0f, 0.0f);
maxCorner = Vec3(0.0f, 0.0f, 0.0f);
return;
}
auto it = positions.begin();
minCorner = it->second;
maxCorner = it->second;
for (const auto& pair : positions) {
const Vec3& pos = pair.second;
minCorner.x = std::min(minCorner.x, pos.x);
minCorner.y = std::min(minCorner.y, pos.y);
minCorner.z = std::min(minCorner.z, pos.z);
maxCorner.x = std::max(maxCorner.x, pos.x);
maxCorner.y = std::max(maxCorner.y, pos.y);
maxCorner.z = std::max(maxCorner.z, pos.z);
}
}
// Get 2D slice of the 3D grid (useful for visualization)
void getSliceAsRGB(int axis, float slicePos,
int& width, int& height, std::vector<int>& rgbData) const {
Vec3 minCorner, maxCorner;
getBoundingBox(minCorner, maxCorner);
// Determine slice dimensions based on axis (0=x, 1=y, 2=z)
if (axis == 0) { // X-slice
width = static_cast<int>(std::ceil(maxCorner.z - minCorner.z)) + 1;
height = static_cast<int>(std::ceil(maxCorner.y - minCorner.y)) + 1;
} else if (axis == 1) { // Y-slice
width = static_cast<int>(std::ceil(maxCorner.z - minCorner.z)) + 1;
height = static_cast<int>(std::ceil(maxCorner.x - minCorner.x)) + 1;
} else { // Z-slice
width = static_cast<int>(std::ceil(maxCorner.x - minCorner.x)) + 1;
height = static_cast<int>(std::ceil(maxCorner.y - minCorner.y)) + 1;
}
// Initialize with black (0,0,0)
rgbData.resize(width * height * 3, 0);
// Fill the slice with object colors
for (const auto& posPair : positions) {
size_t id = posPair.first;
const Vec3& pos = posPair.second;
// Check if position is within slice tolerance
float tolerance = 0.5f; // Half voxel tolerance
bool inSlice = false;
int gridX = 0, gridY = 0;
if (axis == 0 && std::abs(pos.x - slicePos) <= tolerance) { // X-slice
gridX = static_cast<int>(pos.z - minCorner.z);
gridY = static_cast<int>(pos.y - minCorner.y);
inSlice = true;
} else if (axis == 1 && std::abs(pos.y - slicePos) <= tolerance) { // Y-slice
gridX = static_cast<int>(pos.z - minCorner.z);
gridY = static_cast<int>(pos.x - minCorner.x);
inSlice = true;
} else if (axis == 2 && std::abs(pos.z - slicePos) <= tolerance) { // Z-slice
gridX = static_cast<int>(pos.x - minCorner.x);
gridY = static_cast<int>(pos.y - minCorner.y);
inSlice = true;
}
if (inSlice && gridX >= 0 && gridX < width && gridY >= 0 && gridY < height) {
const Vec4& color = getColor(id);
int index = (gridY * width + gridX) * 3;
// Convert float color [0,1] to int [0,255]
rgbData[index] = static_cast<int>(color.r * 255);
rgbData[index + 1] = static_cast<int>(color.g * 255);
rgbData[index + 2] = static_cast<int>(color.b * 255);
}
}
}
void getRegionAsRGB(float minX, float minY, float minZ, float maxX, float maxY, float maxZ,
int& width, int& height, std::vector<int>& rgbData) const {
// For 3D, this creates a 2D projection (XY plane at average Z)
if (minX >= maxX || minY >= maxY || minZ >= maxZ) {
width = 0;
height = 0;
rgbData.clear();
return;
}
// Calculate grid dimensions for XY projection
width = static_cast<int>(std::ceil(maxX - minX));
height = static_cast<int>(std::ceil(maxY - minY));
// Initialize with black (0,0,0)
rgbData.resize(width * height * 3, 0);
// Fill the grid with object colors in the region (XY projection)
for (const auto& posPair : positions) {
size_t id = posPair.first;
const Vec3& pos = posPair.second;
// Check if position is within the region
if (pos.x >= minX && pos.x < maxX &&
pos.y >= minY && pos.y < maxY &&
pos.z >= minZ && pos.z < maxZ) {
// Convert world position to grid coordinates (XY projection)
int gridX = static_cast<int>(pos.x - minX);
int gridY = static_cast<int>(pos.y - minY);
if (gridX >= 0 && gridX < width && gridY >= 0 && gridY < height) {
const Vec4& color = getColor(id);
int index = (gridY * width + gridX) * 3;
// Convert float color [0,1] to int [0,255]
rgbData[index] = static_cast<int>(color.r * 255);
rgbData[index + 1] = static_cast<int>(color.g * 255);
rgbData[index + 2] = static_cast<int>(color.b * 255);
}
}
}
}
void getRegionAsRGB(const Vec3& minCorner, const Vec3& maxCorner,
int& width, int& height, std::vector<int>& rgbData) const {
getRegionAsRGB(minCorner.x, minCorner.y, minCorner.z,
maxCorner.x, maxCorner.y, maxCorner.z,
width, height, rgbData);
}
// Spatial grid methods for 3D
std::tuple<int, int, int> worldToGrid(const Vec3& pos) const {
return {
static_cast<int>(std::floor(pos.x / cellSize)),
static_cast<int>(std::floor(pos.y / cellSize)),
static_cast<int>(std::floor(pos.z / cellSize))
};
}
void updateSpatialIndex(size_t id, const Vec3& oldPos, const Vec3& newPos) {
auto oldCell = worldToGrid(oldPos);
auto newCell = worldToGrid(newPos);
if (oldCell != newCell) {
// Remove from old cell
auto oldIt = spatialGrid.find(oldCell);
if (oldIt != spatialGrid.end()) {
oldIt->second.erase(id);
if (oldIt->second.empty()) {
spatialGrid.erase(oldIt);
}
}
// Add to new cell
spatialGrid[newCell].insert(id);
cellIndices[id] = newCell;
}
}
std::vector<size_t> getIndicesInRadius(const Vec3& position, float radius) const {
std::vector<size_t> result;
Vec3 minPos(position.x - radius, position.y - radius, position.z - radius);
Vec3 maxPos(position.x + radius, position.y + radius, position.z + radius);
auto minCell = worldToGrid(minPos);
auto maxCell = worldToGrid(maxPos);
float radiusSq = radius * radius;
// Only check relevant cells
for (int x = std::get<0>(minCell); x <= std::get<0>(maxCell); ++x) {
for (int y = std::get<1>(minCell); y <= std::get<1>(maxCell); ++y) {
for (int z = std::get<2>(minCell); z <= std::get<2>(maxCell); ++z) {
auto cell = std::make_tuple(x, y, z);
auto it = spatialGrid.find(cell);
if (it != spatialGrid.end()) {
for (size_t id : it->second) {
const Vec3& objPos = getPosition(id);
float dx = objPos.x - position.x;
float dy = objPos.y - position.y;
float dz = objPos.z - position.z;
if (dx * dx + dy * dy + dz * dz <= radiusSq) {
result.push_back(id);
}
}
}
}
}
}
return result;
}
std::vector<size_t> getIndicesInRegion(const Vec3& minCorner, const Vec3& maxCorner) const {
std::vector<size_t> result;
auto minCell = worldToGrid(minCorner);
auto maxCell = worldToGrid(maxCorner);
for (int x = std::get<0>(minCell); x <= std::get<0>(maxCell); ++x) {
for (int y = std::get<1>(minCell); y <= std::get<1>(maxCell); ++y) {
for (int z = std::get<2>(minCell); z <= std::get<2>(maxCell); ++z) {
auto cell = std::make_tuple(x, y, z);
auto it = spatialGrid.find(cell);
if (it != spatialGrid.end()) {
for (size_t id : it->second) {
const Vec3& pos = getPosition(id);
if (pos.x >= minCorner.x && pos.x <= maxCorner.x &&
pos.y >= minCorner.y && pos.y <= maxCorner.y &&
pos.z >= minCorner.z && pos.z <= maxCorner.z) {
result.push_back(id);
}
}
}
}
}
}
return result;
}
size_t getSpatialGridCellCount() const { return spatialGrid.size(); }
size_t getSpatialGridObjectCount() const { return cellIndices.size(); }
float getCellSize() const { return cellSize; }
// 3D-specific utility methods
size_t getVoxelCount() const { return positions.size(); }
// Get density information (useful for volume rendering)
std::vector<float> getDensityGrid(int resX, int resY, int resZ) const {
std::vector<float> density(resX * resY * resZ, 0.0f);
Vec3 minCorner, maxCorner;
getBoundingBox(minCorner, maxCorner);
Vec3 gridSize = maxCorner - minCorner;
if (gridSize.x <= 0 || gridSize.y <= 0 || gridSize.z <= 0) {
return density;
}
Vec3 voxelSize(gridSize.x / resX, gridSize.y / resY, gridSize.z / resZ);
for (const auto& posPair : positions) {
const Vec3& pos = posPair.second;
// Convert to grid coordinates
int gx = static_cast<int>((pos.x - minCorner.x) / gridSize.x * resX);
int gy = static_cast<int>((pos.y - minCorner.y) / gridSize.y * resY);
int gz = static_cast<int>((pos.z - minCorner.z) / gridSize.z * resZ);
if (gx >= 0 && gx < resX && gy >= 0 && gy < resY && gz >= 0 && gz < resZ) {
density[gz * resX * resY + gy * resX + gx] += 1.0f;
}
}
return density;
}
};
#endif