diff options
| -rw-r--r-- | Userland/Libraries/LibGfx/Painter.cpp | 84 |
1 files changed, 37 insertions, 47 deletions
diff --git a/Userland/Libraries/LibGfx/Painter.cpp b/Userland/Libraries/LibGfx/Painter.cpp index 6fc5ca1c9c..685d94af07 100644 --- a/Userland/Libraries/LibGfx/Painter.cpp +++ b/Userland/Libraries/LibGfx/Painter.cpp @@ -1841,27 +1841,6 @@ void Painter::for_each_line_segment_on_bezier_curve(const FloatPoint& control_po for_each_line_segment_on_bezier_curve(control_point, p1, p2, callback); } -static bool can_approximate_elliptical_arc(const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& center, const FloatPoint radii, float x_axis_rotation, float theta_1, float theta_delta) -{ - constexpr static float tolerance = 0.3f; - - auto half_theta_delta = theta_delta / 2.0f; - - auto xc = cosf(x_axis_rotation); - auto xs = sinf(x_axis_rotation); - auto tc = cosf(theta_1 + half_theta_delta); - auto ts = sinf(theta_1 + half_theta_delta); - - auto x2 = xc * radii.x() * tc - xs * radii.y() * ts + center.x(); - auto y2 = xs * radii.x() * tc + xc * radii.y() * ts + center.y(); - - auto ellipse_mid_point = FloatPoint { x2, y2 }; - auto line_mid_point = p1 + (p2 - p1) / 2.0f; - - auto v = ellipse_mid_point.distance_from(line_mid_point); - return v < tolerance; -} - void Painter::draw_quadratic_bezier_curve(const IntPoint& control_point, const IntPoint& p1, const IntPoint& p2, Color color, int thickness, LineStyle style) { VERIFY(scale() == 1); // FIXME: Add scaling support. @@ -1874,40 +1853,51 @@ void Painter::draw_quadratic_bezier_curve(const IntPoint& control_point, const I // static void Painter::for_each_line_segment_on_elliptical_arc(const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& center, const FloatPoint radii, float x_axis_rotation, float theta_1, float theta_delta, Function<void(const FloatPoint&, const FloatPoint&)>& callback) { - struct SegmentDescriptor { - FloatPoint p1; - FloatPoint p2; - float theta; - float theta_delta; - }; + if (radii.x() <= 0 || radii.y() <= 0) + return; - static constexpr auto split_elliptical_arc = [](const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& center, const FloatPoint radii, float x_axis_rotation, float theta_1, float theta_delta, auto& segments) { - auto half_theta_delta = theta_delta / 2; - auto theta_mid = theta_1 + half_theta_delta; + auto start = p1; + auto end = p2; - auto xc = cosf(x_axis_rotation); - auto xs = sinf(x_axis_rotation); - auto tc = cosf(theta_1 + half_theta_delta); - auto ts = sinf(theta_1 + half_theta_delta); + if (theta_delta < 0) { + swap(start, end); + theta_1 = theta_1 + theta_delta; + theta_delta = fabs(theta_delta); + } + + auto relative_start = start - center; + + auto a = radii.x(); + auto b = radii.y(); - auto x2 = xc * radii.x() * tc - xs * radii.y() * ts + center.x(); - auto y2 = xs * radii.x() * tc + xc * radii.y() * ts + center.y(); + // The segments are at most 1 long + auto largest_radius = max(a, b); + double theta_step = atan(1 / (double)largest_radius); - FloatPoint mid_point = { x2, y2 }; + FloatPoint current_point = relative_start; + FloatPoint next_point = { 0, 0 }; - segments.enqueue({ p1, mid_point, theta_1, half_theta_delta }); - segments.enqueue({ mid_point, p2, theta_mid, half_theta_delta }); + auto sin_x_axis = sinf(x_axis_rotation); + auto cos_x_axis = cosf(x_axis_rotation); + auto rotate_point = [sin_x_axis, cos_x_axis](FloatPoint& p) { + auto original_x = p.x(); + auto original_y = p.y(); + + p.set_x(original_x * cos_x_axis - original_y * sin_x_axis); + p.set_y(original_x * sin_x_axis + original_y * cos_x_axis); }; - Queue<SegmentDescriptor> segments; - segments.enqueue({ p1, p2, theta_1, theta_delta }); - while (!segments.is_empty()) { - auto segment = segments.dequeue(); - if (can_approximate_elliptical_arc(segment.p1, segment.p2, center, radii, x_axis_rotation, segment.theta, segment.theta_delta)) - callback(segment.p1, segment.p2); - else - split_elliptical_arc(segment.p1, segment.p2, center, radii, x_axis_rotation, segment.theta, segment.theta_delta, segments); + for (double theta = theta_1; theta <= ((double)theta_1 + (double)theta_delta); theta += theta_step) { + next_point.set_x(a * cosf(theta)); + next_point.set_y(b * sinf(theta)); + rotate_point(next_point); + + callback(current_point + center, next_point + center); + + current_point = next_point; } + + callback(current_point + center, end); } // static |