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stupidsimcpp/util/grid/grid3.hpp
Yggdrasil75 044c059c1d asdf
2026-01-08 10:45:43 -05:00

280 lines
9.4 KiB
C++

#ifndef GRID3_HPP
#define GRID3_HPP
#include <unordered_map>
#include "../vectorlogic/vec3.hpp"
#include "../vectorlogic/vec4.hpp"
#include "../timing_decorator.hpp"
#include "../output/frame.hpp"
#include "../noise/pnoise2.hpp"
#include "../vecmat/mat4.hpp"
#include <vector>
#include <algorithm>
#include "../basicdefines.hpp"
struct Voxel {
//float active;
bool active;
//Vec3f position;
Vec3ui8 color;
};
struct Camera {
Ray3f posfor;
Vec3f up;
float fov;
Camera(Vec3f pos, Vec3f viewdir, Vec3f up, float fov = 80) : posfor(Ray3f(pos, viewdir)), up(up), fov(fov) {}
};
class VoxelGrid {
private:
double binSize = 1;
Vec3i gridSize;
//int width, height, depth;
std::vector<Voxel> voxels;
float radians(float rads) {
return rads * (M_PI / 180);
}
static Mat4f lookAt(const Vec3f& eye, const Vec3f& center, const Vec3f& up) {
Vec3f const f = (center - eye).normalized();
Vec3f const s = f.cross(up).normalized();
Vec3f const u = s.cross(f);
Mat4f Result = Mat4f::identity();
Result(0, 0) = s.x;
Result(1, 0) = s.y;
Result(2, 0) = s.z;
Result(3, 0) = -s.dot(eye);
Result(0, 1) = u.x;
Result(1, 1) = u.y;
Result(2, 1) = u.z;
Result(3, 1) = -u.dot(eye);
Result(0, 2) = -f.x;
Result(1, 2) = -f.y;
Result(2, 2) = -f.z;
Result(3, 2) = f.dot(eye);
return Result;
}
static Mat4f perspective(float fovy, float aspect, float zNear, float zfar) {
float const tanhalfF = tan(fovy / 2);
Mat4f Result = 0;
Result(0,0) = 1 / (aspect * tanhalfF);
Result(1,1) = 1 / tanhalfF;
Result(2,2) = zfar / (zNear - zfar);
Result(2,3) = -1;
Result(3,2) = -(zfar * zNear) / (zfar - zNear);
return Result;
}
public:
VoxelGrid() : gridSize(0,0,0) {
std::cout << "creating empty grid." << std::endl;
}
VoxelGrid(int w, int h, int d) : gridSize(w,h,d) {
voxels.resize(w * h * d);
}
Voxel& get(int x, int y, int z) {
return voxels[z * gridSize.x * gridSize.y + y * gridSize.x + x];
}
const Voxel& get(int x, int y, int z) const {
return voxels[z * gridSize.x * gridSize.y + y * gridSize.x + x];
}
Voxel& get(const Vec3i& xyz) {
return voxels[xyz.z * gridSize.x * gridSize.y + xyz.y * gridSize.x + xyz.x];
}
void resize(int newW, int newH, int newD) {
std::vector<Voxel> newVoxels(newW * newH * newD);
int copyW = std::min(static_cast<int>(gridSize.x), newW);
int copyH = std::min(static_cast<int>(gridSize.y), newH);
int copyD = std::min(static_cast<int>(gridSize.z), newD);
for (int z = 0; z < copyD; ++z) {
for (int y = 0; y < copyH; ++y) {
int oldRowStart = z * gridSize.x * gridSize.y + y * gridSize.x;
int newRowStart = z * newW * newH + y * newW;
std::copy(
voxels.begin() + oldRowStart,
voxels.begin() + oldRowStart + copyW,
newVoxels.begin() + newRowStart
);
}
}
voxels = std::move(newVoxels);
gridSize = Vec3i(newW, newH, newD);
}
void set(int x, int y, int z, bool active, Vec3ui8 color) {
set(Vec3i(x,y,z), active, color);
}
void set(Vec3i pos, bool active, Vec3ui8 color) {
if (pos.x >= 0 || pos.y >= 0 || pos.z >= 0) {
if (!(pos.x < gridSize.x)) {
resize(pos.x, gridSize.y, gridSize.z);
}
else if (!(pos.y < gridSize.y)) {
resize(gridSize.x, pos.y, gridSize.z);
}
else if (!(pos.z < gridSize.z)) {
resize(gridSize.x, gridSize.y, pos.z);
}
Voxel& v = get(pos);
v.active = active; // std::clamp(active, 0.0f, 1.0f);
v.color = color;
}
}
void set(Vec3i pos, Vec4ui8 rgbaval) {
set(pos, static_cast<float>(rgbaval.a / 255), rgbaval.toVec3());
}
template<typename T>
bool inGrid(Vec3<T> voxl) {
return (voxl >= 0 && voxl.x < gridSize.x && voxl.y < gridSize.y && voxl.z < gridSize.z);
}
void voxelTraverse(const Vec3d& origin, const Vec3d& end, std::vector<Vec3i>& visitedVoxel) {
Vec3i cv = (origin / binSize).floorToI();
Vec3i lv = (end / binSize).floorToI();
Vec3d ray = end - origin;
Vec3f step = Vec3f(ray.x >= 0 ? 1 : -1, ray.y >= 0 ? 1 : -1, ray.z >= 0 ? 1 : -1);
Vec3d nextVox = cv.toDouble() + step * binSize;
Vec3d tMax = Vec3d(ray.x != 0 ? (nextVox.x - origin.x) / ray.x : INF,
ray.y != 0 ? (nextVox.y - origin.y) / ray.y : INF,
ray.z != 0 ? (nextVox.z-origin.z) / ray.z : INF);
Vec3d tDelta = Vec3d(ray.x != 0 ? binSize / ray.x * step.x : INF,
ray.y != 0 ? binSize / ray.y * step.y : INF,
ray.z != 0 ? binSize / ray.z * step.z : INF);
Vec3i diff(0,0,0);
bool negRay = false;
if (cv.x != lv.x && ray.x < 0) {
diff.x = diff.x--;
negRay = true;
}
if (cv.y != lv.y && ray.y < 0) {
diff.y = diff.y--;
negRay = true;
}
if (cv.z != lv.z && ray.z < 0) {
diff.z = diff.z--;
negRay = true;
}
if (negRay) {
cv += diff;
visitedVoxel.push_back(cv);
}
while (lv != cv && inGrid(cv)) {
if (get(cv).active) {
visitedVoxel.push_back(cv);
}
if (tMax.x < tMax.y) {
if (tMax.x < tMax.z) {
cv.x += step.x;
tMax.x += tDelta.x;
} else {
cv.z += step.z;
tMax.z += tDelta.z;
}
} else {
if (tMax.y < tMax.z) {
cv.y += step.y;
tMax.y += tDelta.y;
} else {
cv.z += step.z;
tMax.z += tDelta.z;
}
}
}
return; // &&visitedVoxel;
}
int getWidth() const {
return gridSize.x;
}
int getHeight() const {
return gridSize.y;
}
int getDepth() const {
return gridSize.z;
}
frame renderFrame(const Vec3f& CamPos, const Vec3f& dir, const Vec3f& up, float fov, int outW, int outH, frame::colormap colorformat = frame::colormap::RGB) {
TIME_FUNCTION;
Vec3f forward = (dir - CamPos).normalized();
Vec3f right = forward.cross(up).normalized();
Vec3f upCor = right.cross(forward).normalized();
float aspect = static_cast<float>(outW) / static_cast<float>(outH);
float fovRad = radians(fov);
float viewH = 2 * tan(fovRad / 2);
float viewW = viewH * aspect;
float maxDist = std::sqrt(gridSize.lengthSquared()) * binSize;
frame outFrame(outH, outW, frame::colormap::RGB);
std::vector<uint8_t> colorBuffer(outW * outH * 3);
std::cout << "a" << std::endl;
#pragma omp parallel for
for (int y = 0; y < outH; y++) {
float v = (static_cast<float>(y) / static_cast<float>(outH - 1)) - 0.5f;
std::cout << "b";
for (int x = 0; x < outW; x++) {
std::vector<Vec3i> hitVoxels;
float u = (static_cast<float>(x) / static_cast<float>(outW - 1)) - 0.5f;
Vec3f rayDirWorld = (forward + right * (u * viewW) + upCor * (v * viewH)).normalized();
Vec3f rayEnd = CamPos + rayDirWorld * maxDist;
Vec3d rayStartGrid = CamPos.toDouble() / binSize;
Vec3d rayEndGrid = rayEnd.toDouble() / binSize;
voxelTraverse(rayStartGrid, rayEndGrid, hitVoxels);
Vec3ui8 hitColor(10, 10, 255);
for (const Vec3i& voxelPos : hitVoxels) {
if (inGrid(voxelPos)) {
const Voxel& voxel = get(voxelPos);
if (voxel.active) {
hitColor = voxel.color;
break;
}
}
}
std::cout << "c";
hitVoxels.clear();
hitVoxels.shrink_to_fit();
// Set pixel color in buffer
switch (colorformat) {
case frame::colormap::RGB: {
int idx = (y * outW + x) * 3;
colorBuffer[idx + 0] = hitColor.x;
colorBuffer[idx + 1] = hitColor.y;
colorBuffer[idx + 2] = hitColor.z;
break;
}
case frame::colormap::BGRA: {
int idx = (y * outW + x) * 4;
colorBuffer[idx + 3] = hitColor.x;
colorBuffer[idx + 2] = hitColor.y;
colorBuffer[idx + 1] = hitColor.z;
colorBuffer[idx + 0] = 1;
break;
}
}
}
std::cout << "b" << std::endl;
}
outFrame.setData(colorBuffer);
std::cout << "d" << std::endl;
return outFrame;
}
};
#endif