Introduce animated crop.

OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal Kiosk.xcscheme

@@ -57,7 +57,7 @@
             isEnabled = "NO">
          </CommandLineArgument>
          <CommandLineArgument
-            argument = "--new=macintosh"
+            argument = "--new=electron"
             isEnabled = "YES">
          </CommandLineArgument>
          <CommandLineArgument

Outputs/CRT/CRT.cpp

@@ -257,19 +257,38 @@ void CRT::advance_cycles(
 					active_rect_.size.width < 0.95 * scan_target_modals_.output_scale.x &&
 					active_rect_.size.height < 0.95 * scan_target_modals_.output_scale.y
 				) {
-					active_rect_.scale(1.05f, 1.05f);
+					active_rect_.scale(1.02f, 1.02f);
 				}
 
 				const auto output_frame = rect_accumulator_.posit(active_rect_);
-				if(output_frame) {
-					scan_target_modals_.visible_area = *output_frame;
+				if(output_frame && *output_frame != posted_rect_) {
+
+					// Lock in any partial animation that has yet to end.
+					const auto animation_time = float(animation_step_) / float(AnimationSteps);
+					previous_posted_rect_ =
+						previous_posted_rect_ * (1.0f - animation_time) +
+						posted_rect_ * animation_time;
+
+					posted_rect_ = *output_frame;
+					animation_step_ = 0;
+				}
+
+				if(animation_step_ <= AnimationSteps) {
+					const auto animation_time = float(animation_step_) / float(AnimationSteps);
+
+					scan_target_modals_.visible_area =
+						previous_posted_rect_ * (1.0f - animation_time) +
+						posted_rect_ * animation_time;
 					scan_target_modals_.visible_area.origin.x /= scan_target_modals_.output_scale.x;
 					scan_target_modals_.visible_area.size.width /= scan_target_modals_.output_scale.x;
 					scan_target_modals_.visible_area.origin.y /= scan_target_modals_.output_scale.y;
 					scan_target_modals_.visible_area.size.height /= scan_target_modals_.output_scale.y;
 					scan_target_->set_modals(scan_target_modals_);
+
+					++animation_step_;
 				}
 
+				// TODO: probably something more gradated.
 				levels_are_interesting_ = level_changes_in_frame_ >= 5;
 			}
 			active_rect_ = Display::Rect(65536.0f, 65536.0f, 0.0f, 0.0f);

Outputs/CRT/CRT.hpp

@@ -370,11 +370,15 @@ private:
 	static constexpr uint8_t DefaultAmplitude = 41;
 
 	// Accumulator for interesting detail from this frame.
-	Outputs::Display::Rect active_rect_, posted_rect_;
+	Outputs::Display::Rect active_rect_;
+	bool frame_is_complete_ = false;
+
+	// Current state of cropping rectangle as communicated onwards.
+	Outputs::Display::Rect posted_rect_, previous_posted_rect_;
 	Numeric::CubicCurve animation_curve_;
+
 	int animation_step_ = 0;
 	static constexpr int AnimationSteps = 25;
-	bool frame_is_complete_ = false;
 
 	bool levels_are_interesting_ = false;
 	int level_changes_in_frame_ = 0;

Outputs/CRT/Internals/RectAccumulator.hpp

@@ -32,7 +32,6 @@ private:
 	struct RectHistory {
 		void push_back(const Display::Rect &rect) {
 			stream_[stream_pointer_] = rect;
-
 			++stream_pointer_;
 			if(stream_pointer_ == n) stream_pointer_ = 0;
 		}
@@ -67,8 +66,9 @@ private:
 		size_t stream_pointer_ = 0;
 	};
 
-	RectHistory<8> unions_;
-	RectHistory<8> candidates_;
+	RectHistory<32> unions_;	// A long record, to try to avoid instability caused by interlaced video, flashing
+								// cursors, etc.
+	RectHistory<28> candidates_;
 };
 
 }

Outputs/ScanTarget.hpp

@@ -79,6 +79,15 @@ struct Rect {
 		);
 	}
 
+	Rect operator +(const Rect &rhs) const {
+		return Rect(
+			origin.x + rhs.origin.x,
+			origin.y + rhs.origin.y,
+			size.width + rhs.size.width,
+			size.height + rhs.size.height
+		);
+	}
+
 	Rect operator /(const float multiplier) const {
 		return Rect(
 			origin.x / multiplier,