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my grid should work. just need minor tests

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Yggdrasil75
2025-12-31 10:49:52 -05:00
parent aed793b6fe
commit c92b5dc203
5 changed files with 251 additions and 49 deletions
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96
util/grid/grid3.hpp
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@@ -18,10 +18,49 @@ struct Voxel {
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:
size_t width, height, depth;
std::vector<Voxel> voxels;
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();
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(size_t w, size_t h, size_t d) : width(w), height(h), depth(d) {
voxels.resize(w * h * d);
@@ -76,6 +115,22 @@ public:
return (voxl >= 0 && voxl.x < width && voxl.y < height && voxl.z < depth);
}
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;
float aspect = imgWidth / imgHeight;
float fovRad = cam.fov * M_PI / 180;
float scale = tan(fovRad * 0.5);
Vec3f rayDirCam = Vec3f(normedX * aspect * scale, normedY * scale, -1).normalized();
Vec3f eye = cam.posfor.origin;
Vec3f center = eye + cam.posfor.direction;
Mat4f viewMat = lookAt(eye, center, cam.up);
Mat4f invViewMat = viewMat.inverse();
Vec3f rayDirWorld = invViewMat.transformDirection(rayDirCam);
return rayDirWorld.normalized();
}
bool rayCast(const Ray3f& ray, float maxDistance, Vec3f hitPos, Vec3f hitNormal, Vec3f& hitColor) {
hitColor = Vec3f(0,0,0);
Vec3f rayDir = ray.direction;
@@ -107,7 +162,6 @@ public:
current voxel.
*/
float tEntry = 0.0;
Vec3f tBMin;
Vec3f tBMax;
tBMin.x = (0.0 - rayOrigin.x) / rayDir.x;
@@ -186,6 +240,46 @@ public:
}
return hit;
}
size_t getWidth() const {
return width;
}
size_t getHeight() const {
return height;
}
size_t getDepth() const {
return depth;
}
void renderOut(std::vector<uint8_t>& output, size_t& outwidth, size_t& outheight, const Camera& cam) {
output.resize(outwidth * outheight * 3);
Vec3f backgroundColor(0.1f, 0.1f, 0.1f);
float maxDistance = std::sqrt(width*width + height*height + depth*depth) * 2.0f;
for (size_t y = 0; y < outheight; y++) {
for (size_t x = 0; x < outwidth; x++) {
Vec3f rayDir = perPixelRayDir(x, y, outwidth, outheight, cam);
Ray3f ray(cam.posfor.origin, rayDir);
Vec3f hitPos;
Vec3f hitNorm;
Vec3f hitColor;
bool hit = rayCast(ray, maxDistance, hitPos, hitNorm, hitColor);
Vec3f finalColor;
if (!hit) {
finalColor = backgroundColor;
} else {
finalColor = hitColor;
}
finalColor = finalColor.clamp(0, 1);
size_t pixelIndex = (y * outwidth + x) * 3;
output[pixelIndex + 0] = static_cast<uint8_t>(finalColor.x * 255);
output[pixelIndex + 1] = static_cast<uint8_t>(finalColor.y * 255);
output[pixelIndex + 2] = static_cast<uint8_t>(finalColor.z * 255);
}
}
}
};
#endif

31
util/vecmat/mat4.hpp
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@@ -320,36 +320,5 @@ inline Mat4<T> operator*(T scalar, const Mat4<T>& mat) {
using Mat4f = Mat4<float>;
using Mat4d = Mat4<double>;
Mat4f lookAt(Vec3f const& eye, Vec3f const& center, Vec3f const& 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;
}
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;
}
#endif

17
util/vectorlogic/vec3.hpp
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@@ -471,22 +471,7 @@ Vec3<T> mix(const Vec3<T>& a, const Vec3<T>& b, const Vec3<bool>& mask) {
mask.x ? b.x : a.x,
mask.y ? b.y : a.y,
mask.z ? b.z : a.z
)
}
template<typename T>
std::pair<Vec3<T>, Vec3<T>> multiMix(const Vec3<T>& a, const Vec3<T>& b, const Vec3<T>& c, const Vec3<T>& d, const Vec3<bool>& mask) {
outa = Vec3<T>(
mask.x ? b.x : a.x,
mask.y ? b.y : a.y,
mask.z ? b.z : a.z
)
outb = Vec3<T>(
mask.x ? d.x : c.x,
mask.y ? d.y : c.y,
mask.z ? d.z : c.z
)
);
}
#endif