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pushing some changes.

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Yggdrasil75
2026-01-13 14:33:23 -05:00
parent 2870be6cf3
commit 082682a339
4 changed files with 271 additions and 36 deletions
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1
tests/g3test2.cpp
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@@ -6,6 +6,7 @@
#include "../util/output/bmpwriter.hpp"
#include "../util/output/frame.hpp"
#include "../util/timing_decorator.cpp"
#include "../util/noise/pnoise2.hpp"
#include "../imgui/imgui.h"
#include "../imgui/backends/imgui_impl_glfw.h"

304
util/grid/grid33.hpp
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@@ -6,7 +6,13 @@
#include <cmath>
#include <iostream>
#include "../vectorlogic/vec3.hpp"
#include "../basicdefines.hpp"
/// @brief Finds the index of the least significant bit set to 1 in a 64-bit integer.
/// @details Uses compiler intrinsics (_BitScanForward64, __builtin_ctzll) where available,
/// falling back to a De Bruijn sequence multiplication lookup for portability.
/// @param v The 64-bit integer to scan.
/// @return The zero-based index of the lowest set bit. Behavior is undefined if v is 0.
static inline uint32_t FindLowestOn(uint64_t v)
{
#if defined(_MSC_VER) && defined(TREEXY_USE_INTRINSICS)
@@ -35,6 +41,11 @@ static inline uint32_t FindLowestOn(uint64_t v)
#endif
}
/// @brief Counts the number of bits set to 1 (population count) in a 64-bit integer.
/// @details Uses compiler intrinsics (__popcnt64, __builtin_popcountll) where available,
/// falling back to a software Hamming weight implementation.
/// @param v The 64-bit integer to count.
/// @return The number of bits set to 1.
inline uint32_t CountOn(uint64_t v)
{
#if defined(_MSC_VER) && defined(_M_X64)
@@ -50,6 +61,8 @@ inline uint32_t CountOn(uint64_t v)
return static_cast<uint32_t>(v);
}
/// @brief A bitmask class for tracking active cells within a specific grid dimension.
/// @tparam LOG2DIM The log base 2 of the dimension size.
template<uint32_t LOG2DIM>
class Mask {
private:
@@ -57,6 +70,8 @@ private:
static constexpr uint32_t WORD_COUNT = SIZE / 64;
uint64_t mWords[WORD_COUNT];
/// @brief Internal helper to find the linear index of the first active bit.
/// @return The index of the first on bit, or SIZE if none are set.
uint32_t findFirstOn() const {
const uint64_t *w = mWords;
uint32_t n = 0;
@@ -67,6 +82,9 @@ private:
return n == WORD_COUNT ? SIZE : (n << 6) + FindLowestOn(*w);
}
/// @brief Internal helper to find the next active bit after a specific index.
/// @param start The index to start searching from (inclusive check, though logic implies sequential access).
/// @return The index of the next on bit, or SIZE if none are found.
uint32_t findNextOn(uint32_t start) const {
uint32_t n = start >> 6;
if (n >= WORD_COUNT) {
@@ -85,26 +103,37 @@ private:
}
public:
/// @brief Returns the memory size of this Mask instance.
static size_t memUsage() {
return sizeof(Mask);
}
/// @brief Returns the total capacity (number of bits) in the mask.
static uint32_t bitCount() {
return SIZE;
}
/// @brief Returns the number of 64-bit words used to store the mask.
static uint32_t wordCount() {
return WORD_COUNT;
}
/// @brief Retrieves a specific 64-bit word from the mask array.
/// @param n The index of the word.
/// @return The word value.
uint64_t getWord(size_t n) const {
return mWords[n];
}
/// @brief Sets a specific 64-bit word in the mask array.
/// @param n The index of the word.
/// @param v The value to set.
void setWord(size_t n, uint64_t v) {
mWords[n] = v;
}
/// @brief Calculates the total number of bits set to 1 in the mask.
/// @return The count of active bits.
uint32_t countOn() const {
uint32_t sum = 0;
uint32_t n = WORD_COUNT;
@@ -114,36 +143,52 @@ public:
return sum;
}
/// @brief Iterator class for traversing set bits in the Mask.
class Iterator {
private:
uint32_t mPos;
const Mask* mParent;
public:
/// @brief Default constructor creating an invalid end iterator.
Iterator() : mPos(Mask::SIZE), mParent(nullptr) {}
/// @brief Constructor for a specific position.
/// @param pos The current bit index.
/// @param parent Pointer to the Mask being iterated.
Iterator(uint32_t pos, const Mask* parent) : mPos(pos), mParent(parent) {}
/// @brief Default assignment operator.
Iterator& operator=(const Iterator&) = default;
/// @brief Dereference operator.
/// @return The index of the current active bit.
uint32_t operator*() const {
return mPos;
}
/// @brief Boolean conversion operator.
/// @return True if the iterator is valid (not at end), false otherwise.
operator bool() const {
return mPos != Mask::SIZE;
}
/// @brief Pre-increment operator. Advances to the next active bit.
/// @return Reference to self.
Iterator& operator++() {
mPos = mParent -> findNextOn(mPos + 1);
return *this;
}
};
/// @brief Default constructor. Initializes all bits to 0 (off).
Mask() {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
mWords[i] = 0;
}
}
/// @brief Constructor initializing all bits to a specific state.
/// @param on If true, all bits are set to 1; otherwise 0.
Mask(bool on) {
const uint64_t v = on ? ~uint64_t(0) : uint64_t(0);
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
@@ -151,17 +196,25 @@ public:
}
}
/// @brief Copy constructor.
Mask(const Mask &other) {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
mWords[i] = other.mWords[i];
}
}
/// @brief Reinterprets internal words as a different type and retrieves one.
/// @tparam WordT The type to cast the pointer to (e.g., uint32_t).
/// @param n The index in the reinterpreted array.
/// @return The value at index n.
template<typename WordT>
WordT getWord(int n) const {
return reinterpret_cast<const WordT *>(mWords)[n];
}
/// @brief Assignment operator.
/// @param other The mask to copy from.
/// @return Reference to self.
Mask &operator=(const Mask &other) {
// static_assert(sizeof(Mask) == sizeof(Mask), "Mismatching sizeof");
// static_assert(WORD_COUNT == Mask::WORD_COUNT, "Mismatching word count");
@@ -174,6 +227,9 @@ public:
return *this;
}
/// @brief Equality operator.
/// @param other The mask to compare.
/// @return True if all bits match, false otherwise.
bool operator==(const Mask &other) const {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
if (mWords[i] != other.mWords[i]) return false;
@@ -181,21 +237,28 @@ public:
return true;
}
/// @brief Inequality operator.
/// @param other The mask to compare.
/// @return True if any bits differ.
bool operator!=(const Mask &other) const {
return !((*this) == other);
}
/// @brief Returns an iterator to the first active bit.
/// @return An Iterator pointing to the first set bit.
Iterator beginOn() const {
return Iterator(this->findFirstOn(), this);
}
/// @brief return true if bit n is set.
/// @param n the bit to check
/// @return true otherwise return false
/// @brief Checks if a specific bit is set.
/// @param n The bit index to check.
/// @return True if the bit is 1, false if 0.
bool isOn(uint32_t n) const {
return 0 != (mWords[n >> 6] & (uint64_t(1) << (n&63)));
}
/// @brief Checks if all bits are set to 1.
/// @return True if fully saturated.
bool isOn() const {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
if (mWords[i] != ~uint64_t(0)) return false;
@@ -203,6 +266,8 @@ public:
return true;
}
/// @brief Checks if all bits are set to 0.
/// @return True if fully empty.
bool isOff() const {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
if (mWords[i] != ~uint64_t(0)) return true;
@@ -210,6 +275,9 @@ public:
return false;
}
/// @brief Sets a specific bit to 1.
/// @param n The bit index to set.
/// @return True if the bit was already on, false otherwise.
bool setOn(uint32_t n) {
uint64_t &word = mWords[n >> 6];
const uint64_t bit = (uint64_t(1) << (n & 63));
@@ -218,10 +286,15 @@ public:
return wasOn;
}
/// @brief Sets a specific bit to 0.
/// @param n The bit index to clear.
void setOff(uint32_t n) {
mWords[n >> 6] &= ~(uint64_t(1) << (n & 63));
}
/// @brief Sets a specific bit to the boolean value `On`.
/// @param n The bit index.
/// @param On The state to set (true=1, false=0).
void set(uint32_t n, bool On) {
#if 1
auto &word = mWords[n >> 6];
@@ -233,18 +306,22 @@ public:
#endif
}
/// @brief Sets all bits to 1.
void setOn() {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
mWords[i] = ~uint64_t(0);
}
}
/// @brief Sets all bits to 0.
void setOff() {
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
mWords[i] = uint64_t(0);
}
}
/// @brief Sets all bits to a specific boolean state.
/// @param on If true, fill with 1s; otherwise 0s.
void set(bool on) {
const uint64_t v = on ? ~uint64_t(0) : uint64_t(0);
for (uint32_t i = 0; i < WORD_COUNT; ++i) {
@@ -252,6 +329,7 @@ public:
}
}
/// @brief Inverts (flips) all bits in the mask.
void toggle() {
uint32_t n = WORD_COUNT;
for (auto* w = mWords; n--; ++w) {
@@ -259,11 +337,16 @@ public:
}
}
/// @brief Inverts (flips) a specific bit.
/// @param n The bit index to toggle.
void toggle(uint32_t n) {
mWords[n >> 6] ^= uint64_t(1) << (n & 63);
}
};
/// @brief Represents a generic grid block containing data and a presence mask.
/// @tparam DataT The type of data stored in each cell.
/// @tparam Log2DIM The log base 2 of the grid dimension (e.g., 3 for 8x8x8).
template <typename DataT, int Log2DIM>
class Grid {
public:
@@ -273,6 +356,11 @@ public:
Mask<Log2DIM> mask;
};
/// @brief A sparse hierarchical voxel grid container.
/// @details Implements a 3-level structure: Root Map -> Inner Grid -> Leaf Grid.
/// @tparam DataT The type of data stored in the leaf voxels.
/// @tparam INNER_BITS Log2 dimension of the inner grid nodes (intermediate layer).
/// @tparam LEAF_BITS Log2 dimension of the leaf grid nodes (data layer).
template <typename DataT, int INNER_BITS = 2, int LEAF_BITS = 3>
class VoxelGrid {
public:
@@ -285,8 +373,12 @@ public:
const double inv_resolution;
const double half_resolution;
/// @brief Constructs a VoxelGrid with a specific voxel size.
/// @param voxel_size The size of a single voxel in world units.
VoxelGrid(double voxel_size) : resolution(voxel_size), inv_resolution(1.0 / voxel_size), half_resolution(0.5 * voxel_size) {}
/// @brief Calculates the approximate memory usage of the grid structure.
/// @return The size in bytes used by the map, inner grids, and leaf grids.
size_t getMemoryUsage() const {
size_t total_size = 0;
for (unsigned i = 0; i < root_map.bucket_count(); ++i) {
@@ -306,6 +398,11 @@ public:
return total_size;
}
/// @brief Converts a 3D float position to integer grid coordinates.
/// @param x X coordinate.
/// @param y Y coordinate.
/// @param z Z coordinate.
/// @return The integer grid coordinates.
static inline Vec3i PosToCoord(float x, float y, float z) {
// union VI {
// __m128i m;
@@ -321,18 +418,32 @@ public:
return Vec3f(x,y,z).floorToI();
}
/// @brief Converts a 3D double position to integer grid coordinates.
/// @param x X coordinate.
/// @param y Y coordinate.
/// @param z Z coordinate.
/// @return The integer grid coordinates.
static inline Vec3i posToCoord(double x, double y, double z) {
return Vec3f(x,y,z).floorToI();
}
/// @brief Converts a Vec3d position to integer grid coordinates.
/// @param pos The position vector.
/// @return The integer grid coordinates.
static inline Vec3i posToCoord(const Vec3d &pos) {
return pos.floorToI();
}
/// @brief Converts integer grid coordinates back to world position (center of voxel).
/// @param coord The grid coordinate.
/// @return The world position center of the voxel.
Vec3d Vec3iToPos(const Vec3i& coord) const {
return (coord.toDouble() * resolution) + half_resolution;
}
/// @brief Iterates over every active cell in the grid and applies a visitor function.
/// @tparam VisitorFunction The type of the callable (DataT& val, Vec3i pos).
/// @param func The function to execute for each active voxel.
template <class VisitorFunction>
void forEachCell(VisitorFunction func) {
constexpr static int32_t MASK_LEAF = ((1 << LEAF_BITS) - 1);
@@ -363,6 +474,7 @@ public:
}
}
/// @brief Helper class to accelerate random access to the VoxelGrid by caching recent paths.
class Accessor {
private:
RootMap &root_;
@@ -371,7 +483,14 @@ public:
InnerGrid* prev_inner_ptr_ = nullptr;
LeafGrid* prev_leaf_ptr_ = nullptr;
public:
/// @brief Constructs an Accessor for a specific root map.
/// @param root Reference to the grid's root map.
Accessor(RootMap& root) : root_(root) {}
/// @brief Sets a value at a specific coordinate, creating nodes if they don't exist.
/// @param coord The grid coordinate.
/// @param value The value to store.
/// @return True if the voxel was already active, false if it was newly activated.
bool setValue(const Vec3i& coord, const DataT& value) {
LeafGrid* leaf_ptr = prev_leaf_ptr_;
const Vec3i inner_key = getInnerKey(coord);
@@ -406,6 +525,9 @@ public:
return was_on;
}
/// @brief Retrieves a pointer to the value at a coordinate.
/// @param coord The grid coordinate.
/// @return Pointer to the data if active, otherwise nullptr.
DataT* value(const Vec3i& coord) {
LeafGrid* leaf_ptr = prev_leaf_ptr_;
const Vec3i inner_key = getInnerKey(coord);
@@ -443,30 +565,45 @@ public:
return &(leaf_ptr->data[leaf_index]);
}
/// @brief Returns the most recently accessed InnerGrid pointer.
/// @return Pointer to the cached InnerGrid.
const InnerGrid* lastInnerGrid() const {
return prev_inner_ptr_;
}
/// @brief Returns the most recently accessed LeafGrid pointer.
/// @return Pointer to the cached LeafGrid.
const LeafGrid* lastLeafGrid() const {
return prev_leaf_ptr_;
}
};
/// @brief Creates a new Accessor instance for this grid.
/// @return An Accessor object.
Accessor createAccessor() {
return Accessor(root_map);
}
/// @brief Computes the key for the RootMap based on global coordinates.
/// @param coord The global grid coordinate.
/// @return The base coordinate for the root key (masked).
static inline Vec3i getRootKey(const Vec3i& coord) {
constexpr static int32_t MASK = ~((1 << Log2N) - 1);
return {coord.x & MASK, coord.y & MASK, coord.z & MASK};
}
/// @brief Computes the key for locating an InnerGrid (intermediate block).
/// @param coord The global grid coordinate.
/// @return The coordinate masked to the InnerGrid resolution.
static inline Vec3i getInnerKey(const Vec3i &coord)
{
constexpr static int32_t MASK = ~((1 << LEAF_BITS) - 1);
return {coord.x & MASK, coord.y & MASK, coord.z & MASK};
}
/// @brief Computes the linear index within an InnerGrid for a given coordinate.
/// @param coord The global grid coordinate.
/// @return The linear index (0 to size of InnerGrid).
static inline uint32_t getInnerIndex(const Vec3i &coord)
{
constexpr static int32_t MASK = ((1 << INNER_BITS) - 1);
@@ -477,6 +614,9 @@ public:
// clang-format on
}
/// @brief Computes the linear index within a LeafGrid for a given coordinate.
/// @param coord The global grid coordinate.
/// @return The linear index (0 to size of LeafGrid).
static inline uint32_t getLeafIndex(const Vec3i &coord)
{
constexpr static int32_t MASK = ((1 << LEAF_BITS) - 1);
@@ -487,55 +627,147 @@ public:
// clang-format on
}
/// @brief Sets the color of a voxel at a specific world position.
/// @details Assumes DataT is compatible with Vec3ui8.
/// @param worldPos The 3D world position.
/// @param color The color value to set.
/// @return True if the voxel previously existed, false if created.
bool setVoxelColor(const Vec3d& worldPos, const Vec3ui8& color) {
Vec3i coord = posToCoord(worldPos);
Accessor accessor = createAccessor();
return accessor.setValue(coord, color);
}
/// @brief Retrieves the color of a voxel at a specific world position.
/// @details Assumes DataT is compatible with Vec3ui8.
/// @param worldPos The 3D world position.
/// @return Pointer to the color if exists, nullptr otherwise.
Vec3ui8* getVoxelColor(const Vec3d& worldPos) {
Vec3i coord = posToCoord(worldPos);
Accessor accessor = createAccessor();
return accessor.value(coord);
}
// Render with projection (simple orthographic projection)
void renderProjectedToRGBBuffer(std::vector<uint8_t>& buffer, int width, int height, const Vec3d& viewDir = Vec3d(0, 0, 1),
const Vec3d& upDir = Vec3d(0, 1, 0)) {
// Clear buffer
buffer.clear();
buffer.resize(width * height * 3, 0);
/// @brief Renders the grid to an RGB buffer
/// @details Iterates all cells and projects them onto a 2D plane defined by viewDir and upDir.
/// @param buffer The output buffer (will be resized to width * height * 3).
/// @param width Width of the output image.
/// @param height Height of the output image.
/// @param viewOrigin the position of the camera
/// @param viewDir The direction the camera is looking.
/// @param upDir The up vector of the camera.
/// @param fov the field of view for the camera
void renderToRGB(std::vector<uint8_t>& buffer, int width, int height, const Vec3d& viewOrigin,
const Vec3d& viewDir, const Vec3d& upDir, float fov = 80) {
// Resize buffer to hold width * height * 3 bytes (RGB)
buffer.resize(width * height * 3);
std::fill(buffer.begin(), buffer.end(), 0);
// Create view matrix (simplified orthographic projection)
Vec3d view = viewDir.normalized();
Vec3d up = upDir.normalized();
Vec3d right = view.cross(up).normalized();
up = right.cross(view).normalized(); // Re-orthogonalize
// Normalize view direction and compute right vector
Vec3d viewDirN = viewDir.normalized();
Vec3d upDirN = upDir.normalized();
Vec3d rightDir = viewDirN.cross(upDirN).normalized();
// For each voxel, project to screen
forEachCell([&](const Vec3ui8& color, const Vec3i& coord) {
// Convert voxel coordinate to world position
Vec3d worldPos = Vec3iToPos(coord);
// Simple orthographic projection: drop view direction component
double xProj = worldPos.dot(right);
double yProj = worldPos.dot(up);
// Normalize to pixel coordinates (assuming unit size)
int px = static_cast<int>((xProj + 0.5) * width);
int py = static_cast<int>((yProj + 0.5) * height);
// Clamp to image bounds
if (px >= 0 && px < width && py >= 0 && py < height) {
int index = (py * width + px) * 3;
// Recompute up vector to ensure orthogonality
Vec3d realUpDir = rightDir.cross(viewDirN).normalized();
// Compute focal length based on FOV
double aspectRatio = static_cast<double>(width) / static_cast<double>(height);
double fovRad = fov * M_PI / 180.0;
double focalLength = 1.0 / tan(fovRad * 0.5);
// Precompute scaling factors for screen coordinates
double pixelWidth = 2.0 / (width - 1);
double pixelHeight = 2.0 / (height - 1);
// Compute half voxel size for accurate ray-voxel intersection
double halfVoxel = resolution * 0.5;
// Create an accessor for efficient voxel lookup
Accessor accessor = createAccessor();
// For each pixel in the output image
for (int y = 0; y < height; ++y) {
for (int x = 0; x < width; ++x) {
// Convert pixel coordinates to normalized device coordinates [-1, 1]
double ndcX = (2.0 * x / (width - 1)) - 1.0;
double ndcY = 1.0 - (2.0 * y / (height - 1)); // Flip Y
Vec3ui8 finalColor = color;
// Scale by aspect ratio
ndcX *= aspectRatio;
// Write RGB
buffer[index] = finalColor.x; // R
buffer[index + 1] = finalColor.y; // G
buffer[index + 2] = finalColor.z; // B
// Compute ray direction in camera space
Vec3d rayDirCam(ndcX, ndcY, focalLength);
// Transform ray direction to world space
Vec3d rayDirWorld = (rightDir * rayDirCam.x) +
(realUpDir * rayDirCam.y) +
(viewDirN * rayDirCam.z);
rayDirWorld = rayDirWorld.normalized();
// Set up ray marching
Vec3d rayPos = viewOrigin;
double maxDistance = 100.0; // Maximum ray distance
double stepSize = resolution; // Step size for ray marching
// Ray marching loop
for (double t = 0; t < maxDistance; t += stepSize) {
rayPos = viewOrigin + rayDirWorld * t;
// Convert world position to voxel coordinate
Vec3i coord = posToCoord(rayPos);
// Look up voxel value using accessor (cached for efficiency)
DataT* voxelData = accessor.value(coord);
if (voxelData) {
// Voxel hit - extract color
// Assuming DataT is Vec3ui8 or compatible
Vec3ui8* colorPtr = reinterpret_cast<Vec3ui8*>(voxelData);
// Get buffer index for this pixel
size_t pixelIdx = (y * width + x) * 3;
// Apply simple shading based on normal
// Estimate normal by checking neighbors
double shading = 1.0;
// Check neighboring voxels to estimate surface normal
Vec3d voxelCenter = Vec3iToPos(coord);
Vec3d toRay = (rayPos - voxelCenter).normalized();
// Simple normal estimation by checking adjacent voxels
Vec3i neighbors[6] = {
Vec3i(coord.x + 1, coord.y, coord.z),
Vec3i(coord.x - 1, coord.y, coord.z),
Vec3i(coord.x, coord.y + 1, coord.z),
Vec3i(coord.x, coord.y - 1, coord.z),
Vec3i(coord.x, coord.y, coord.z + 1),
Vec3i(coord.x, coord.y, coord.z - 1)
};
// Count empty neighbors to estimate surface orientation
int emptyCount = 0;
for (int i = 0; i < 6; ++i) {
if (!accessor.value(neighbors[i])) {
emptyCount++;
}
}
// Simple shading: more visible if fewer neighbors (edge/corner)
if (emptyCount > 0) {
shading = 0.7 + 0.3 * (emptyCount / 6.0);
}
// Store color in buffer with shading
buffer[pixelIdx] = static_cast<uint8_t>(colorPtr->x * shading);
buffer[pixelIdx + 1] = static_cast<uint8_t>(colorPtr->y * shading);
buffer[pixelIdx + 2] = static_cast<uint8_t>(colorPtr->z * shading);
break; // Stop ray marching after hitting first voxel
}
}
}
});
}
}
};

1
util/noise/pnoise2.hpp
View File

@@ -8,6 +8,7 @@
#include <random>
#include "../vectorlogic/vec2.hpp"
#include "../vectorlogic/vec3.hpp"
#include "../vectorlogic/vec4.hpp"
#include "../timing_decorator.hpp"
class PNoise2 {

1
util/vectorlogic/vec3.hpp
View File

@@ -459,6 +459,7 @@ public:
using Vec3f = Vec3<float>;
using Vec3d = Vec3<double>;
using Vec3i = Vec3<int>;
using Vec3i32 = Vec3<uint32_t>;
using Vec3i8 = Vec3<int8_t>;
using Vec3ui8 = Vec3<uint8_t>;
using Vec3T = Vec3<size_t>;