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pushing some stuff home

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Yggdrasil75
2026-01-02 15:01:34 -05:00
parent 7bc711a3ad
commit 57e9834772
2 changed files with 241 additions and 118 deletions
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200
util/grid/grid3.hpp
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@@ -29,7 +29,10 @@ class VoxelGrid {
private:
size_t width, height, depth;
std::vector<Voxel> voxels;
float radians(float rads) {
return rads * (M_PI / 180);
}
static Mat4f lookAt(Vec3f const& eye, Vec3f const& center, Vec3f const& up) {
Vec3f const f = (center - eye).normalized();
Vec3f const s = f.cross(up).normalized();
@@ -115,6 +118,15 @@ public:
return (voxl >= 0 && voxl.x < width && voxl.y < height && voxl.z < depth);
}
std::vector<Vec3f> genPixelDirs(Vec3f pos, Vec3f dir, size_t imgWidth, size_t imgHeight, float fov) {
std::vector<Vec3f> dirs(imgWidth * imgHeight);
float fovRad = radians(fov);
float tanFov = tan(fovRad * 0.5);
float aspect = static_cast<float>(imgWidth) / static_cast<float>(imgHeight);
Vec3f worldUp(0, 1, 0);
Vec3f camRight = worldUp.cross(dir).normalized();
}
Vec3f perPixelRayDir(size_t x, size_t y, size_t imgWidth, size_t imgHeight, const Camera& cam) const {
float normedX = (x + 0.5) / imgWidth * 2 - 1;
float normedY = 1 - (y+0.5) / imgHeight * 2;
@@ -142,68 +154,71 @@ public:
step.z = (rayDir.z > 0) ? 1 : -1;
Vec3f tMax;
Vec3f tDelta;
bool startOut = false;
//initialization
tDelta.x = std::abs(1.0 / rayDir.x);
tDelta.y = std::abs(1.0 / rayDir.y);
tDelta.z = std::abs(1.0 / rayDir.z);
tMax = mix(((rayOrigin - currentVoxel.toFloat()) / -rayDir).toFloat(), (((currentVoxel.toFloat() + 1) - rayOrigin) / rayDir).toFloat(), rayDir.mask([](float x, float value) { return x > 0; }, 0));
tMax = mix(((rayOrigin - currentVoxel.toFloat()) / -rayDir).toFloat(),
(((currentVoxel.toFloat() + 1) - rayOrigin) / rayDir).toFloat(),
rayDir.mask([](float x, float value) { return x > 0; }, 0));
if (!inGrid(rayOrigin)) {
/*
The initialization phase begins by identifying the voxel in which the ray origin, →
u, is found. If the ray origin is outside the grid, we find the point in which the ray enters the grid and take the adjacent voxel. The integer
variables X and Y are initialized to the starting voxel coordinates. In addition, the variables stepX and
stepY are initialized to either 1 or -1 indicating whether X and Y are incremented or decremented as the
ray crosses voxel boundaries (this is determined by the sign of the x and y components of →
v).
Next, we determine the value of t at which the ray crosses the first vertical voxel boundary and
store it in variable tMaxX. We perform a similar computation in y and store the result in tMaxY. The
minimum of these two values will indicate how much we can travel along the ray and still remain in the
current voxel.
*/
startOut = true;
Vec3f tBMin;
Vec3f tBMax;
tBMin.x = (0.0 - rayOrigin.x) / rayDir.x;
tBMax.x = (width - rayOrigin.x) / rayDir.x;
if (tBMin.x > tBMax.x) std::swap(tBMin.x, tBMax.x);
tBMin.y = (0.0 - rayOrigin.y) / rayDir.y;
tBMax.y = (height - rayOrigin.y) / rayDir.y;
if (tBMin.y > tBMax.y) std::swap(tBMin.y, tBMax.y);
tBMin.z = (0.0 - rayOrigin.z) / rayDir.z;
tBMax.z = (depth - rayOrigin.z) / rayDir.z;
if (tBMin.z > tBMax.z) std::swap(tBMin.z, tBMax.z);
float tEntry = tBMin.maxComp();
float tExit = tBMax.minComp();
if (tEntry > tExit || tExit < 0.0) return false;
if (tEntry < 0.0) tEntry = 0.0;
if (tEntry > 0.0) {
rayOrigin = rayOrigin + rayDir * tEntry;
currentVoxel = rayOrigin.floorToT();
tMax = mix(((currentVoxel.toFloat() + 1) - rayOrigin) / rayDir, (rayOrigin - currentVoxel) / -rayDir, rayDir.mask([](float x, float value) { return x > 0; }, 0) );
tMax = mix(((currentVoxel.toFloat() + 1) - rayOrigin) / rayDir,
(rayOrigin - currentVoxel) / -rayDir,
rayDir.mask([](float x, float value) { return x > 0; }, 0));
}
}
// if (startOut && !inGrid(currentVoxel)) {
// std::cout << "grid edge not found. " << currentVoxel << std::endl;
// }
float aalpha = 0.0;
bool hit = false;
float tDist = 0.0;
/*
Finally, we compute tDeltaX and tDeltaY. TDeltaX indicates how far along the ray we must move
(in units of t) for the horizontal component of such a movement to equal the width of a voxel. Similarly,
we store in tDeltaY the amount of movement along the ray which has a vertical component equal to the
height of a voxel.
*/
// Main DDA loop
while (inGrid(currentVoxel) && tDist < maxDistance) {
Voxel& voxel = get(currentVoxel);
// Ignore alpha - treat any voxel with active > 0 as solid
if (voxel.active > EPSILON) {
Vec3f voxelColor(static_cast<float>(voxel.color.x / 255.0), static_cast<float>(voxel.color.y / 255.0), static_cast<float>(voxel.color.z / 255.0));
float contribution = voxel.active * (1.0 - aalpha);
hitColor = hitColor + voxelColor * contribution;
aalpha += contribution;
// Convert color from 0-255 to 0-1 range
Vec3f voxelColor(
static_cast<float>(voxel.color.x / 255.0),
static_cast<float>(voxel.color.y / 255.0),
static_cast<float>(voxel.color.z / 255.0)
);
// No alpha blending - just take the first solid voxel's color
hitColor = voxelColor;
hitPos = rayOrigin + rayDir * tDist;
// Determine which face was hit
if (tMax.x <= tMax.y && tMax.x <= tMax.z) {
hitNormal = Vec3f(-step.x, 0.0, 0.0);
} else if (tMax.y <= tMax.x && tMax.y <= tMax.z) {
@@ -211,11 +226,11 @@ public:
} else {
hitNormal = Vec3f(0.0, 0.0, -step.z);
}
}
if (aalpha > EPSILON) {
hit = true;
return true; // Return immediately on first solid hit
}
// Move to next voxel
if (tMax.x < tMax.y) {
if (tMax.x < tMax.z) {
tDist = tMax.x;
@@ -238,11 +253,124 @@ public:
}
}
}
if (aalpha > EPSILON) {
std::cout << "hit at: " << currentVoxel << " with value of " << aalpha << std::endl;
}
return hit;
return false;
}
// bool rayCast(const Ray3f& ray, float maxDistance, Vec3f hitPos, Vec3f hitNormal, Vec3f& hitColor) {
// hitColor = Vec3f(0,0,0);
// Vec3f rayDir = ray.direction;
// Vec3f rayOrigin = ray.origin;
// Vec3T currentVoxel = rayOrigin.floorToT();
// Vec3i step;
// step.x = (rayDir.x > 0) ? 1 : -1;
// step.y = (rayDir.y > 0) ? 1 : -1;
// step.z = (rayDir.z > 0) ? 1 : -1;
// Vec3f tMax;
// Vec3f tDelta;
// bool startOut = false;
// tDelta.x = std::abs(1.0 / rayDir.x);
// tDelta.y = std::abs(1.0 / rayDir.y);
// tDelta.z = std::abs(1.0 / rayDir.z);
// tMax = mix(((rayOrigin - currentVoxel.toFloat()) / -rayDir).toFloat(), (((currentVoxel.toFloat() + 1) - rayOrigin) / rayDir).toFloat(), rayDir.mask([](float x, float value) { return x > 0; }, 0));
// if (!inGrid(rayOrigin)) {
// startOut = true;
// /*
// The initialization phase begins by identifying the voxel in which the ray origin, →
// u, is found. If the ray origin is outside the grid, we find the point in which the ray enters the grid and take the adjacent voxel. The integer
// variables X and Y are initialized to the starting voxel coordinates. In addition, the variables stepX and
// stepY are initialized to either 1 or -1 indicating whether X and Y are incremented or decremented as the
// ray crosses voxel boundaries (this is determined by the sign of the x and y components of →
// v).
// Next, we determine the value of t at which the ray crosses the first vertical voxel boundary and
// store it in variable tMaxX. We perform a similar computation in y and store the result in tMaxY. The
// minimum of these two values will indicate how much we can travel along the ray and still remain in the
// current voxel.
// */
// Vec3f tBMin;
// Vec3f tBMax;
// tBMin.x = (0.0 - rayOrigin.x) / rayDir.x;
// tBMax.x = (width - rayOrigin.x) / rayDir.x;
// if (tBMin.x > tBMax.x) std::swap(tBMin.x, tBMax.x);
// tBMin.y = (0.0 - rayOrigin.y) / rayDir.y;
// tBMax.y = (height - rayOrigin.y) / rayDir.y;
// if (tBMin.y > tBMax.y) std::swap(tBMin.y, tBMax.y);
// tBMin.z = (0.0 - rayOrigin.z) / rayDir.z;
// tBMax.z = (depth - rayOrigin.z) / rayDir.z;
// if (tBMin.z > tBMax.z) std::swap(tBMin.z, tBMax.z);
// float tEntry = tBMin.maxComp();
// float tExit = tBMax.minComp();
// if (tEntry > tExit || tExit < 0.0) return false;
// if (tEntry < 0.0) tEntry = 0.0;
// if (tEntry > 0.0) {
// rayOrigin = rayOrigin + rayDir * tEntry;
// currentVoxel = rayOrigin.floorToT();
// tMax = mix(((currentVoxel.toFloat() + 1) - rayOrigin) / rayDir, (rayOrigin - currentVoxel) / -rayDir, rayDir.mask([](float x, float value) { return x > 0; }, 0) );
// }
// }
// if (startOut && !inGrid(currentVoxel)) std::cout << "grid edge not found. " << currentVoxel << std::endl;
// float aalpha = 0.0;
// bool hit = false;
// float tDist = 0.0;
// /*
// Finally, we compute tDeltaX and tDeltaY. TDeltaX indicates how far along the ray we must move
// (in units of t) for the horizontal component of such a movement to equal the width of a voxel. Similarly,
// we store in tDeltaY the amount of movement along the ray which has a vertical component equal to the
// height of a voxel.
// */
// while (inGrid(currentVoxel) && tDist < maxDistance) {
// Voxel& voxel = get(currentVoxel);
// if (voxel.active > EPSILON) {
// Vec3f voxelColor(static_cast<float>(voxel.color.x / 255.0), static_cast<float>(voxel.color.y / 255.0), static_cast<float>(voxel.color.z / 255.0));
// float contribution = voxel.active * (1.0 - aalpha);
// hitColor = hitColor + voxelColor * contribution;
// aalpha += contribution;
// hitPos = rayOrigin + rayDir * tDist;
// if (tMax.x <= tMax.y && tMax.x <= tMax.z) {
// hitNormal = Vec3f(-step.x, 0.0, 0.0);
// } else if (tMax.y <= tMax.x && tMax.y <= tMax.z) {
// hitNormal = Vec3f(0.0, -step.y, 0.0);
// } else {
// hitNormal = Vec3f(0.0, 0.0, -step.z);
// }
// }
// if (aalpha > EPSILON) {
// hit = true;
// }
// if (tMax.x < tMax.y) {
// if (tMax.x < tMax.z) {
// tDist = tMax.x;
// tMax.x += tDelta.x;
// currentVoxel.x += step.x;
// } else {
// tDist = tMax.z;
// tMax.z += tDelta.z;
// currentVoxel.z += step.z;
// }
// } else {
// if (tMax.y < tMax.z) {
// tDist = tMax.y;
// tMax.y += tDelta.y;
// currentVoxel.y += step.y;
// } else {
// tDist = tMax.z;
// tMax.z += tDelta.z;
// currentVoxel.z += step.z;
// }
// }
// }
// // if (aalpha > EPSILON) {
// // std::cout << "hit at: " << currentVoxel << " with value of " << aalpha << std::endl;
// // }
// return hit;
// }
size_t getWidth() const {
return width;