Move geometry lib to frc971/vision

Going to use for target mapping. Previously used this for 2022 vision.

Signed-off-by: Milind Upadhyay <milind.upadhyay@gmail.com>
Change-Id: Ifd9d13d3f9b0ea1aac42fb6c96ef2a5062b9f637
diff --git a/y2022/vision/BUILD b/y2022/vision/BUILD
index 6325234..233465e 100644
--- a/y2022/vision/BUILD
+++ b/y2022/vision/BUILD
@@ -121,7 +121,6 @@
         ":blob_detector_lib",
         ":calibration_data",
         ":calibration_fbs",
-        ":geometry_lib",
         ":target_estimate_fbs",
         ":target_estimator_lib",
         "//aos:flatbuffer_merge",
@@ -217,31 +216,6 @@
 )
 
 cc_library(
-    name = "geometry_lib",
-    hdrs = [
-        "geometry.h",
-    ],
-    target_compatible_with = ["@platforms//os:linux"],
-    visibility = ["//y2022:__subpackages__"],
-    deps = [
-        "//aos/util:math",
-        "//third_party:opencv",
-        "@com_github_google_glog//:glog",
-    ],
-)
-
-cc_test(
-    name = "geometry_test",
-    srcs = [
-        "geometry_test.cc",
-    ],
-    deps = [
-        ":geometry_lib",
-        "//aos/testing:googletest",
-    ],
-)
-
-cc_library(
     name = "blob_detector_lib",
     srcs = [
         "blob_detector.cc",
@@ -252,9 +226,9 @@
     target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2022:__subpackages__"],
     deps = [
-        ":geometry_lib",
         "//aos/network:team_number",
         "//aos/time",
+        "//frc971/vision:geometry_lib",
         "//third_party:opencv",
     ],
 )
@@ -276,6 +250,7 @@
         "//aos/logging",
         "//aos/time",
         "//frc971/control_loops:quaternion_utils",
+        "//frc971/vision:geometry_lib",
         "//third_party:opencv",
         "//y2022:constants",
         "@com_google_absl//absl/strings:str_format",
diff --git a/y2022/vision/blob_detector.cc b/y2022/vision/blob_detector.cc
index 2f90513..3893ed6 100644
--- a/y2022/vision/blob_detector.cc
+++ b/y2022/vision/blob_detector.cc
@@ -6,10 +6,10 @@
 
 #include "aos/network/team_number.h"
 #include "aos/time/time.h"
+#include "frc971/vision/geometry.h"
 #include "opencv2/features2d.hpp"
 #include "opencv2/highgui/highgui.hpp"
 #include "opencv2/imgproc.hpp"
-#include "y2022/vision/geometry.h"
 
 DEFINE_bool(
     use_outdoors, true,
@@ -140,7 +140,7 @@
   constexpr double kMaxBlobAngle = M_PI - kMinBlobAngle;
   std::vector<std::vector<cv::Point>> blob_circle;
   std::vector<BlobStats> blob_circle_stats;
-  Circle circle;
+  frc971::vision::Circle circle;
 
   // If we see more than this number of blobs after filtering based on
   // color/size, the circle fit may detect noise so just return no blobs.
@@ -165,9 +165,10 @@
           filtered_blobs[j], filtered_blobs[k], filtered_blobs[l]};
       std::vector<BlobStats> current_stats{filtered_stats[j], filtered_stats[k],
                                            filtered_stats[l]};
-      const std::optional<Circle> current_circle =
-          Circle::Fit({current_stats[0].centroid, current_stats[1].centroid,
-                       current_stats[2].centroid});
+      const std::optional<frc971::vision::Circle> current_circle =
+          frc971::vision::Circle::Fit({current_stats[0].centroid,
+                                       current_stats[1].centroid,
+                                       current_stats[2].centroid});
 
       // Make sure that a circle could be created from the points
       if (!current_circle) {
diff --git a/y2022/vision/geometry.h b/y2022/vision/geometry.h
deleted file mode 100644
index c27eb4d..0000000
--- a/y2022/vision/geometry.h
+++ /dev/null
@@ -1,136 +0,0 @@
-#ifndef Y2022_VISION_GEOMETRY_H_
-#define Y2022_VISION_GEOMETRY_H_
-
-#include "aos/util/math.h"
-#include "glog/logging.h"
-#include "opencv2/core/types.hpp"
-
-namespace y2022::vision {
-
-// Linear equation in the form y = mx + b
-struct SlopeInterceptLine {
-  double m, b;
-
-  inline SlopeInterceptLine(cv::Point2d p, cv::Point2d q) {
-    if (p.x == q.x) {
-      CHECK_EQ(p.y, q.y) << "Can't fit line to infinite slope";
-
-      // If two identical points were passed in, give the slope 0,
-      // with it passing the point.
-      m = 0.0;
-    } else {
-      m = (p.y - q.y) / (p.x - q.x);
-    }
-    // y = mx + b -> b = y - mx
-    b = p.y - (m * p.x);
-  }
-
-  inline double operator()(double x) const { return (m * x) + b; }
-};
-
-// Linear equation in the form ax + by = c
-struct StdFormLine {
- public:
-  double a, b, c;
-
-  inline std::optional<cv::Point2d> Intersection(const StdFormLine &l) const {
-    // Use Cramer's rule to solve for the intersection
-    const double denominator = Determinant(a, b, l.a, l.b);
-    const double numerator_x = Determinant(c, b, l.c, l.b);
-    const double numerator_y = Determinant(a, c, l.a, l.c);
-
-    std::optional<cv::Point2d> intersection = std::nullopt;
-    // Return nullopt if the denominator is 0, meaning the same slopes
-    if (denominator != 0) {
-      intersection =
-          cv::Point2d(numerator_x / denominator, numerator_y / denominator);
-    }
-
-    return intersection;
-  }
-
- private:  // Determinant of [[a, b], [c, d]]
-  static inline double Determinant(double a, double b, double c, double d) {
-    return (a * d) - (b * c);
-  }
-};
-
-struct Circle {
- public:
-  cv::Point2d center;
-  double radius;
-
-  static inline std::optional<Circle> Fit(std::vector<cv::Point2d> points) {
-    CHECK_EQ(points.size(), 3ul);
-    // For the 3 points, we have 3 equations in the form
-    // (x - h)^2 + (y - k)^2 = r^2
-    // Manipulate them to solve for the center and radius
-    // (x1 - h)^2 + (y1 - k)^2 = r^2 ->
-    // x1^2 + h^2 - 2x1h + y1^2 + k^2 - 2y1k = r^2
-    // Also, (x2 - h)^2 + (y2 - k)^2 = r^2
-    // Subtracting these two, we get
-    // x1^2 - x2^2 - 2h(x1 - x2) + y1^2 - y2^2 - 2k(y1 - y2) = 0 ->
-    // h(x1 - x2) + k(y1 - y2) = (-x1^2 + x2^2 - y1^2 + y2^2) / -2
-    // Doing the same with equations 1 and 3, we get the second linear equation
-    // h(x1 - x3) + k(y1 - y3) = (-x1^2 + x3^2 - y1^2 + y3^2) / -2
-    // Now, we can solve for their intersection and find the center
-    const auto l =
-        StdFormLine{points[0].x - points[1].x, points[0].y - points[1].y,
-                    (-std::pow(points[0].x, 2) + std::pow(points[1].x, 2) -
-                     std::pow(points[0].y, 2) + std::pow(points[1].y, 2)) /
-                        -2.0};
-    const auto m =
-        StdFormLine{points[0].x - points[2].x, points[0].y - points[2].y,
-                    (-std::pow(points[0].x, 2) + std::pow(points[2].x, 2) -
-                     std::pow(points[0].y, 2) + std::pow(points[2].y, 2)) /
-                        -2.0};
-    const auto center = l.Intersection(m);
-
-    std::optional<Circle> circle = std::nullopt;
-    if (center) {
-      // Now find the radius
-      const double radius = cv::norm(points[0] - *center);
-      circle = Circle{*center, radius};
-    }
-    return circle;
-  }
-
-  inline double DistanceTo(cv::Point2d p) const {
-    const auto p_prime = TranslateToOrigin(p);
-    // Now, the distance is simply the difference between distance from the
-    // origin to p' and the radius.
-    return std::abs(cv::norm(p_prime) - radius);
-  }
-
-  inline double AngleOf(cv::Point2d p) const {
-    auto p_prime = TranslateToOrigin(p);
-    // Flip the y because y values go downwards.
-    p_prime.y *= -1;
-    return std::atan2(p_prime.y, p_prime.x);
-  }
-
-  // Expects all angles to be from 0 to 2pi
-  // TODO(milind): handle wrapping
-  static inline bool AngleInRange(double theta, double theta_min,
-                                  double theta_max) {
-    return (
-        (theta >= theta_min && theta <= theta_max) ||
-        (theta_min > theta_max && (theta >= theta_min || theta <= theta_max)));
-  }
-
-  inline bool InAngleRange(cv::Point2d p, double theta_min,
-                           double theta_max) const {
-    return AngleInRange(AngleOf(p), theta_min, theta_max);
-  }
-
- private:
-  // Translate the point on the circle
-  // as if the circle's center is the origin (0,0)
-  inline cv::Point2d TranslateToOrigin(cv::Point2d p) const {
-    return cv::Point2d(p.x - center.x, p.y - center.y);
-  }
-};
-
-}  // namespace y2022::vision
-
-#endif  // Y2022_VISION_GEOMETRY_H_
diff --git a/y2022/vision/geometry_test.cc b/y2022/vision/geometry_test.cc
deleted file mode 100644
index 0a5a759..0000000
--- a/y2022/vision/geometry_test.cc
+++ /dev/null
@@ -1,111 +0,0 @@
-#include "y2022/vision/geometry.h"
-
-#include <cmath>
-
-#include "aos/util/math.h"
-#include "glog/logging.h"
-#include "gtest/gtest.h"
-
-namespace y2022::vision::testing {
-
-TEST(GeometryTest, SlopeInterceptLine) {
-  // Test a normal line
-  {
-    SlopeInterceptLine l({2.0, 3.0}, {4.0, 2.0});
-    EXPECT_DOUBLE_EQ(l.m, -0.5);
-    EXPECT_DOUBLE_EQ(l.b, 4.0);
-    EXPECT_DOUBLE_EQ(l(5), 1.5);
-  }
-  // Test a horizontal line
-  {
-    SlopeInterceptLine l({2.0, 3.0}, {4.0, 3.0});
-    EXPECT_DOUBLE_EQ(l.m, 0.0);
-    EXPECT_DOUBLE_EQ(l.b, 3.0);
-    EXPECT_DOUBLE_EQ(l(1000.0), 3.0);
-  }
-  // Test duplicate points
-  {
-    SlopeInterceptLine l({2.0, 3.0}, {2.0, 3.0});
-    EXPECT_DOUBLE_EQ(l.m, 0.0);
-    EXPECT_DOUBLE_EQ(l.b, 3.0);
-    EXPECT_DOUBLE_EQ(l(1000.0), 3.0);
-  }
-  // Test infinite slope
-  {
-    EXPECT_DEATH(SlopeInterceptLine({2.0, 3.0}, {2.0, 5.0}),
-                 "(.*)infinite slope(.*)");
-  }
-}
-
-TEST(GeometryTest, StdFormLine) {
-  // Test the intersection of normal lines
-  {
-    StdFormLine l{3.0, 2.0, 2.3};
-    StdFormLine m{-2.0, 1.2, -0.3};
-    const cv::Point2d kIntersection = {42.0 / 95.0, 37.0 / 76.0};
-    EXPECT_EQ(*l.Intersection(m), kIntersection);
-    EXPECT_EQ(*m.Intersection(l), kIntersection);
-  }
-  // Test the intersection of parallel lines
-  {
-    StdFormLine l{-3.0, 2.0, -3.7};
-    StdFormLine m{-6.0, 4.0, 0.1};
-    EXPECT_EQ(l.Intersection(m), std::nullopt);
-    EXPECT_EQ(m.Intersection(l), std::nullopt);
-  }
-  // Test the intersection of duplicate lines
-  {
-    StdFormLine l{6.0, -8.0, 0.23};
-    StdFormLine m{6.0, -8.0, 0.23};
-    EXPECT_EQ(l.Intersection(m), std::nullopt);
-    EXPECT_EQ(m.Intersection(l), std::nullopt);
-  }
-}
-
-TEST(GeometryTest, Circle) {
-  // Test fitting a normal circle
-  {
-    auto c = Circle::Fit({{-6.0, 3.2}, {-3.0, 2.0}, {-9.3, 1.4}});
-    EXPECT_TRUE(c.has_value());
-    EXPECT_NEAR(c->center.x, -5.901, 1e-3);
-    EXPECT_NEAR(c->center.y, -0.905, 1e-3);
-    EXPECT_NEAR(c->radius, 4.106, 1e-3);
-
-    // Coordinate systems flipped because of image
-    const cv::Point2d kPoint = {c->center.x - c->radius * std::sqrt(3.0) / 2.0,
-                                c->center.y - c->radius / 2.0};
-    EXPECT_NEAR(c->AngleOf(kPoint), 5.0 * M_PI / 6.0, 1e-5);
-    EXPECT_TRUE(c->InAngleRange(kPoint, 4.0 * M_PI / 6.0, M_PI));
-    EXPECT_FALSE(c->InAngleRange(kPoint, 0, 2.0 * M_PI / 6.0));
-    EXPECT_EQ(c->DistanceTo(kPoint), 0.0);
-
-    const cv::Point2d kZeroPoint = {c->center.x + c->radius, c->center.y};
-    EXPECT_NEAR(c->AngleOf(kZeroPoint), 0.0, 1e-5);
-    EXPECT_TRUE(c->InAngleRange(kZeroPoint, (2.0 * M_PI) - 0.1, 0.1));
-    EXPECT_EQ(c->DistanceTo(kZeroPoint), 0.0);
-
-    // Test the distance to another point
-    const cv::Point2d kDoubleDistPoint = {
-        c->center.x - (c->radius * 2.0) * std::sqrt(3.0) / 2.0,
-        c->center.y - (c->radius * 2.0) / 2.0};
-    EXPECT_DOUBLE_EQ(c->DistanceTo(kDoubleDistPoint), c->radius);
-
-    // Distance to center should be radius
-    EXPECT_DOUBLE_EQ(c->DistanceTo(c->center), c->radius);
-  }
-  // Test fitting an invalid circle (duplicate points)
-  {
-    auto c = Circle::Fit({{-6.0, 3.2}, {-3.0, 2.0}, {-6.0, 3.2}});
-    EXPECT_FALSE(c.has_value());
-  }
-  // Test if angles are in ranges
-  {
-    EXPECT_TRUE(Circle::AngleInRange(0.5, 0.4, 0.6));
-    EXPECT_TRUE(Circle::AngleInRange(0, (2.0 * M_PI) - 0.2, 0.2));
-    EXPECT_FALSE(
-        Circle::AngleInRange(0, (2.0 * M_PI) - 0.2, (2.0 * M_PI) - 0.1));
-    EXPECT_TRUE(Circle::AngleInRange(0.5, (2.0 * M_PI) - 0.1, 0.6));
-  }
-}
-
-}  // namespace y2022::vision::testing
diff --git a/y2022/vision/target_estimator.cc b/y2022/vision/target_estimator.cc
index 1447d81..9bbaf75 100644
--- a/y2022/vision/target_estimator.cc
+++ b/y2022/vision/target_estimator.cc
@@ -4,7 +4,7 @@
 #include "aos/time/time.h"
 #include "ceres/ceres.h"
 #include "frc971/control_loops/quaternion_utils.h"
-#include "geometry.h"
+#include "frc971/vision/geometry.h"
 #include "opencv2/core/core.hpp"
 #include "opencv2/core/eigen.hpp"
 #include "opencv2/features2d.hpp"
@@ -156,9 +156,9 @@
 
   CHECK_GE(blob_stats_.size(), 3) << "Expected at least 3 blobs";
 
-  const auto circle =
-      Circle::Fit({blob_stats_[0].centroid, blob_stats_[1].centroid,
-                   blob_stats_[2].centroid});
+  const auto circle = frc971::vision::Circle::Fit({blob_stats_[0].centroid,
+                                                   blob_stats_[1].centroid,
+                                                   blob_stats_[2].centroid});
   CHECK(circle.has_value());
 
   max_blob_area_ = 0.0;