Factors out the Apple II/IIe video switches and mode selection logic.

Machines/Apple/AppleII/Video.cpp

@@ -11,9 +11,9 @@
 using namespace Apple::II::Video;
 
 VideoBase::VideoBase(bool is_iie, std::function<void(Cycles)> &&target) :
+	VideoSwitches<Cycles>(Cycles(2), std::move(target)),
 	crt_(910, 1, Outputs::Display::Type::NTSC60, Outputs::Display::InputDataType::Luminance1),
-	is_iie_(is_iie),
+	is_iie_(is_iie) {
-	deferrer_(std::move(target)) {
 
 	// Show only the centre 75% of the TV frame.
 	crt_.set_display_type(Outputs::Display::DisplayType::CompositeColour);
@@ -59,97 +59,20 @@ Outputs::Display::DisplayType VideoBase::get_display_type() const {
 	return crt_.get_display_type();
 }
 
-/*
+void VideoBase::did_set_alternative_character_set(bool alternative_character_set) {
-	Rote setters and getters.
+	alternative_character_set_ = alternative_character_set;
-*/
+	if(alternative_character_set) {
-void VideoBase::set_alternative_character_set(bool alternative_character_set) {
+		character_zones[1].address_mask = 0xff;
-	set_alternative_character_set_ = alternative_character_set;
+		character_zones[1].xor_mask = 0;
-	deferrer_.defer(Cycles(2), [this, alternative_character_set] {
+	} else {
-		alternative_character_set_ = alternative_character_set;
+		character_zones[1].address_mask = 0x3f;
-		if(alternative_character_set) {
+		character_zones[1].xor_mask = flash_mask();
-			character_zones[1].address_mask = 0xff;
+		// The XOR mask is seeded here; it's dynamic, so updated elsewhere.
-			character_zones[1].xor_mask = 0;
+	}
-		} else {
-			character_zones[1].address_mask = 0x3f;
-			character_zones[1].xor_mask = flash_mask();
-		}
-	});
 }
 
-bool VideoBase::get_alternative_character_set() {
+void VideoBase::did_set_annunciator_3(bool annunciator_3) {
-	return set_alternative_character_set_;
+	high_resolution_mask_ = annunciator_3 ? 0x7f : 0xff;
-}
-
-void VideoBase::set_80_columns(bool columns_80) {
-	set_columns_80_ = columns_80;
-	deferrer_.defer(Cycles(2), [this, columns_80] {
-		columns_80_ = columns_80;
-	});
-}
-
-bool VideoBase::get_80_columns() {
-	return set_columns_80_;
-}
-
-void VideoBase::set_80_store(bool store_80) {
-	set_store_80_ = store_80_ = store_80;
-}
-
-bool VideoBase::get_80_store() {
-	return set_store_80_;
-}
-
-void VideoBase::set_page2(bool page2) {
-	set_page2_ = page2_ = page2;
-}
-
-bool VideoBase::get_page2() {
-	return set_page2_;
-}
-
-void VideoBase::set_text(bool text) {
-	set_text_ = text;
-	deferrer_.defer(Cycles(2), [this, text] {
-		text_ = text;
-	});
-}
-
-bool VideoBase::get_text() {
-	return set_text_;
-}
-
-void VideoBase::set_mixed(bool mixed) {
-	set_mixed_ = mixed;
-	deferrer_.defer(Cycles(2), [this, mixed] {
-		mixed_ = mixed;
-	});
-}
-
-bool VideoBase::get_mixed() {
-	return set_mixed_;
-}
-
-void VideoBase::set_high_resolution(bool high_resolution) {
-	set_high_resolution_ = high_resolution;
-	deferrer_.defer(Cycles(2), [this, high_resolution] {
-		high_resolution_ = high_resolution;
-	});
-}
-
-bool VideoBase::get_high_resolution() {
-	return set_high_resolution_;
-}
-
-void VideoBase::set_annunciator_3(bool annunciator_3) {
-	set_annunciator_3_ = annunciator_3;
-	deferrer_.defer(Cycles(2), [this, annunciator_3] {
-		annunciator_3_ = annunciator_3;
-		high_resolution_mask_ = annunciator_3_ ? 0x7f : 0xff;
-	});
-}
-
-bool VideoBase::get_annunciator_3() {
-	return set_annunciator_3_;
 }
 
 void VideoBase::set_character_rom(const std::vector<uint8_t> &character_rom) {

Machines/Apple/AppleII/Video.hpp

@@ -13,6 +13,8 @@
 #include "../../../ClockReceiver/ClockReceiver.hpp"
 #include "../../../ClockReceiver/DeferredQueue.hpp"
 
+#include "VideoSwitches.hpp"
+
 #include <array>
 #include <vector>
 
@@ -33,7 +35,7 @@ class BusHandler {
 		}
 };
 
-class VideoBase {
+class VideoBase: public VideoSwitches<Cycles> {
 	public:
 		VideoBase(bool is_iie, std::function<void(Cycles)> &&target);
 
@@ -49,109 +51,6 @@ class VideoBase {
 		/// Gets the type of output.
 		Outputs::Display::DisplayType get_display_type() const;
 
-		/*
-			Descriptions for the setters below are taken verbatim from
-			the Apple IIe Technical Reference. Addresses are the conventional
-			locations within the Apple II memory map. Only those which affect
-			video output are implemented here.
-
-			Those registers which don't exist on a II/II+ are marked.
-		*/
-
-		/*!
-			Setter for ALTCHAR ($C00E/$C00F; triggers on write only):
-
-			* Off: display text using primary character set.
-			* On: display text using alternate character set.
-
-			Doesn't exist on a II/II+.
-		*/
-		void set_alternative_character_set(bool);
-		bool get_alternative_character_set();
-
-		/*!
-			Setter for 80COL ($C00C/$C00D; triggers on write only).
-
-			* Off: display 40 columns.
-			* On: display 80 columns.
-
-			Doesn't exist on a II/II+.
-		*/
-		void set_80_columns(bool);
-		bool get_80_columns();
-
-		/*!
-			Setter for 80STORE ($C000/$C001; triggers on write only).
-
-			* Off: cause PAGE2 to select auxiliary RAM.
-			* On: cause PAGE2 to switch main RAM areas.
-
-			Doesn't exist on a II/II+.
-		*/
-		void set_80_store(bool);
-		bool get_80_store();
-
-		/*!
-			Setter for PAGE2 ($C054/$C055; triggers on read or write).
-
-			* Off: select Page 1.
-			* On: select Page 2 or, if 80STORE on, Page 1 in auxiliary memory.
-
-			80STORE doesn't exist on a II/II+; therefore this always selects
-			either Page 1 or Page 2 on those machines.
-		*/
-		void set_page2(bool);
-		bool get_page2();
-
-		/*!
-			Setter for TEXT ($C050/$C051; triggers on read or write).
-
-			* Off: display graphics or, if MIXED on, mixed.
-			* On: display text.
-		*/
-		void set_text(bool);
-		bool get_text();
-
-		/*!
-			Setter for MIXED ($C052/$C053; triggers on read or write).
-
-			* Off: display only text or only graphics.
-			* On: if TEXT off, display text and graphics.
-		*/
-		void set_mixed(bool);
-		bool get_mixed();
-
-		/*!
-			Setter for HIRES ($C056/$C057; triggers on read or write).
-
-			* Off: if TEXT off, display low-resolution graphics.
-			* On: if TEXT off, display high-resolution or, if DHIRES on, double high-resolution graphics.
-
-			DHIRES doesn't exist on a II/II+; therefore this always selects
-			either high- or low-resolution graphics on those machines.
-
-			Despite Apple's documentation, the IIe also supports double low-resolution
-			graphics, which are the 80-column analogue to ordinary low-resolution 40-column
-			low-resolution graphics.
-		*/
-		void set_high_resolution(bool);
-		bool get_high_resolution();
-
-		/*!
-			Setter for annunciator 3.
-
-			* On: turn on annunciator 3.
-			* Off: turn off annunciator 3.
-
-			This exists on both the II/II+ and the IIe, but has no effect on
-			video on the older machines. It's intended to be used on the IIe
-			to confirm double-high resolution mode but has side effects in
-			selecting mixed mode output and discarding high-resolution
-			delay bits.
-		*/
-		void set_annunciator_3(bool);
-		bool get_annunciator_3();
-
 		// Setup for text mode.
 		void set_character_rom(const std::vector<uint8_t> &);
 
@@ -167,28 +66,9 @@ class VideoBase {
 			return uint8_t((flash_ / flash_length) * 0xff);
 		}
 
-		// Enumerates all Apple II and IIe display modes.
+		bool alternative_character_set_ = false;
-		enum class GraphicsMode {
+		void did_set_annunciator_3(bool) override;
-			Text = 0,
+		void did_set_alternative_character_set(bool) override;
-			DoubleText,
-			HighRes,
-			DoubleHighRes,
-			LowRes,
-			DoubleLowRes,
-			FatLowRes
-		};
-		bool is_text_mode(GraphicsMode m) { return m <= GraphicsMode::DoubleText; }
-		bool is_double_mode(GraphicsMode m) { return !!(int(m)&1); }
-
-		// Various soft-switch values.
-		bool alternative_character_set_ = false, set_alternative_character_set_ = false;
-		bool columns_80_ = false, set_columns_80_ = false;
-		bool store_80_ = false, set_store_80_ = false;
-		bool page2_ = false, set_page2_ = false;
-		bool text_ = true, set_text_ = true;
-		bool mixed_ = false, set_mixed_ = false;
-		bool high_resolution_ = false, set_high_resolution_ = false;
-		bool annunciator_3_ = false, set_annunciator_3_ = false;
 
 		// Graphics carry is the final level output in a fetch window;
 		// it carries on into the next if it's high resolution with
@@ -208,7 +88,7 @@ class VideoBase {
 		std::array<uint8_t, 40> base_stream_;
 		std::array<uint8_t, 40> auxiliary_stream_;
 
-		bool is_iie_ = false;
+		const bool is_iie_ = false;
 		static constexpr int flash_length = 8406;
 
 		// Describes the current text mode mapping from in-memory character index
@@ -256,9 +136,6 @@ class VideoBase {
 			clock rather than the 14M.
 		*/
 		void output_fat_low_resolution(uint8_t *target, const uint8_t *source, size_t length, int column, int row) const;
-
-		// Maintain a DeferredQueue for delayed mode switches.
-		DeferredQueuePerformer<Cycles> deferrer_;
 };
 
 template <class BusHandler, bool is_iie> class Video: public VideoBase {
@@ -268,13 +145,6 @@ template <class BusHandler, bool is_iie> class Video: public VideoBase {
 			VideoBase(is_iie, [this] (Cycles cycles) { advance(cycles); }),
 			bus_handler_(bus_handler) {}
 
-		/*!
-			Runs video for @c cycles.
-		*/
-		void run_for(Cycles cycles) {
-			deferrer_.run_for(cycles);
-		}
-
 		/*!
 			Obtains the last value the video read prior to time now+offset.
 		*/
@@ -345,7 +215,7 @@ template <class BusHandler, bool is_iie> class Video: public VideoBase {
 
 				A frame is oriented around 65 cycles across, 262 lines down.
 			*/
-			constexpr int first_sync_line = 220;		// A complete guess. Information needed.
+			constexpr int first_sync_line = 220;	// A complete guess. Information needed.
 			constexpr int first_sync_column = 49;	// Also a guess.
 			constexpr int sync_length = 4;			// One of the two likely candidates.
 
@@ -422,7 +292,7 @@ template <class BusHandler, bool is_iie> class Video: public VideoBase {
 							const int pixel_end = std::min(40, ending_column);
 							const int pixel_row = row_ & 7;
 
-							const bool is_double = Video::is_double_mode(line_mode);
+							const bool is_double = is_double_mode(line_mode);
 							if(!is_double && was_double_ && pixel_pointer_) {
 								pixel_pointer_[pixel_start*14 + 0] =
 								pixel_pointer_[pixel_start*14 + 1] =
@@ -585,35 +455,6 @@ template <class BusHandler, bool is_iie> class Video: public VideoBase {
 			}
 		}
 
-		GraphicsMode graphics_mode(int row) {
-			if(
-				text_ ||
-				(mixed_ && row >= 160 && row < 192)
-			) return columns_80_ ? GraphicsMode::DoubleText : GraphicsMode::Text;
-			if(high_resolution_) {
-				return (annunciator_3_ && columns_80_) ? GraphicsMode::DoubleHighRes : GraphicsMode::HighRes;
-			} else {
-				if(columns_80_) return GraphicsMode::DoubleLowRes;
-				if(annunciator_3_) return GraphicsMode::FatLowRes;
-				return GraphicsMode::LowRes;
-			}
-		}
-
-		int video_page() {
-			return (store_80_ || !page2_) ? 0 : 1;
-		}
-
-		uint16_t get_row_address(int row) {
-			const int character_row = row >> 3;
-			const int pixel_row = row & 7;
-			const uint16_t row_address = uint16_t((character_row >> 3) * 40 + ((character_row&7) << 7));
-
-			const GraphicsMode pixel_mode = graphics_mode(row);
-			return ((pixel_mode == GraphicsMode::HighRes) || (pixel_mode == GraphicsMode::DoubleHighRes)) ?
-				uint16_t(((video_page()+1) * 0x2000) + row_address + ((pixel_row&7) << 10)) :
-				uint16_t(((video_page()+1) * 0x400) + row_address);
-		}
-
 		BusHandler &bus_handler_;
 };
 

Machines/Apple/AppleII/VideoSwitches.hpp

@@ -0,0 +1,254 @@
+//
+//  VideoSwitches.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 31/10/2020.
+//  Copyright © 2020 Thomas Harte. All rights reserved.
+//
+
+#ifndef VideoSwitches_h
+#define VideoSwitches_h
+
+#include "../../../ClockReceiver/ClockReceiver.hpp"
+#include "../../../ClockReceiver/DeferredQueue.hpp"
+
+namespace Apple {
+namespace II {
+
+// Enumerates all Apple II, IIe and IIgs display modes.
+enum class GraphicsMode {
+	Text = 0,
+	DoubleText,
+	HighRes,
+	DoubleHighRes,
+	LowRes,
+	DoubleLowRes,
+	FatLowRes
+};
+constexpr bool is_text_mode(GraphicsMode m) { return m <= GraphicsMode::DoubleText; }
+constexpr bool is_double_mode(GraphicsMode m) { return int(m) & 1; }
+
+template <typename TimeUnit> class VideoSwitches {
+	public:
+		/*!
+			Constructs a new instance of VideoSwitches in which changes to the switch
+			affect the video mode only after @c delay cycles.
+		*/
+		VideoSwitches(TimeUnit delay, std::function<void(TimeUnit)> &&target) : delay_(delay), deferrer_(std::move(target)) {}
+
+		/*!
+			Advances @c cycles.
+		*/
+		void run_for(TimeUnit cycles) {
+			deferrer_.run_for(cycles);
+		}
+
+		/*
+			Descriptions for the setters below are taken verbatim from
+			the Apple IIe Technical Reference. Addresses are the conventional
+			locations within the Apple II memory map. Only those which affect
+			video output are implemented here.
+
+			Those registers which don't exist on a II/II+ are marked.
+		*/
+
+		/*!
+			Setter for ALTCHAR ($C00E/$C00F; triggers on write only):
+
+			* Off: display text using primary character set.
+			* On: display text using alternate character set.
+
+			Doesn't exist on a II/II+.
+		*/
+		void set_alternative_character_set(bool alternative_character_set) {
+			external_.alternative_character_set = alternative_character_set;
+			deferrer_.defer(delay_, [this, alternative_character_set] {
+				internal_.alternative_character_set = alternative_character_set;
+				did_set_annunciator_3(alternative_character_set);
+			});
+		}
+		bool get_alternative_character_set() const {
+			return external_.alternative_character_set;
+		}
+
+		/*!
+			Setter for 80COL ($C00C/$C00D; triggers on write only).
+
+			* Off: display 40 columns.
+			* On: display 80 columns.
+
+			Doesn't exist on a II/II+.
+		*/
+		void set_80_columns(bool columns_80) {
+			external_.columns_80 = columns_80;
+			deferrer_.defer(delay_, [this, columns_80] {
+				internal_.columns_80 = columns_80;
+			});
+		}
+		bool get_80_columns() const {
+			return external_.columns_80;
+		}
+
+		/*!
+			Setter for 80STORE ($C000/$C001; triggers on write only).
+
+			* Off: cause PAGE2 to select auxiliary RAM.
+			* On: cause PAGE2 to switch main RAM areas.
+
+			Doesn't exist on a II/II+.
+		*/
+		void set_80_store(bool store_80) {
+			external_.store_80 = internal_.store_80 = store_80;
+		}
+		bool get_80_store() const {
+			return external_.store_80;
+		}
+
+		/*!
+			Setter for PAGE2 ($C054/$C055; triggers on read or write).
+
+			* Off: select Page 1.
+			* On: select Page 2 or, if 80STORE on, Page 1 in auxiliary memory.
+
+			80STORE doesn't exist on a II/II+; therefore this always selects
+			either Page 1 or Page 2 on those machines.
+		*/
+		void set_page2(bool page2) {
+			external_.page2 = internal_.page2 = page2;
+		}
+		bool get_page2() const {
+			return external_.page2;
+		}
+
+		/*!
+			Setter for TEXT ($C050/$C051; triggers on read or write).
+
+			* Off: display graphics or, if MIXED on, mixed.
+			* On: display text.
+		*/
+		void set_text(bool text) {
+			external_.text = text;
+			deferrer_.defer(delay_, [this, text] {
+				internal_.text = text;
+			});
+		}
+		bool get_text() const {
+			return external_.text;
+		}
+
+		/*!
+			Setter for MIXED ($C052/$C053; triggers on read or write).
+
+			* Off: display only text or only graphics.
+			* On: if TEXT off, display text and graphics.
+		*/
+		void set_mixed(bool mixed) {
+			external_.mixed = mixed;
+			deferrer_.defer(delay_, [this, mixed] {
+				internal_.mixed = mixed;
+			});
+		}
+		bool get_mixed() const {
+			return external_.mixed;
+		}
+
+		/*!
+			Setter for HIRES ($C056/$C057; triggers on read or write).
+
+			* Off: if TEXT off, display low-resolution graphics.
+			* On: if TEXT off, display high-resolution or, if DHIRES on, double high-resolution graphics.
+
+			DHIRES doesn't exist on a II/II+; therefore this always selects
+			either high- or low-resolution graphics on those machines.
+
+			Despite Apple's documentation, the IIe also supports double low-resolution
+			graphics, which are the 80-column analogue to ordinary low-resolution 40-column
+			low-resolution graphics.
+		*/
+		void set_high_resolution(bool high_resolution) {
+			external_.high_resolution = high_resolution;
+			deferrer_.defer(delay_, [this, high_resolution] {
+				internal_.high_resolution = high_resolution;
+			});
+		}
+		bool get_high_resolution() const {
+			return external_.high_resolution;
+		}
+
+		/*!
+			Setter for annunciator 3.
+
+			* On: turn on annunciator 3.
+			* Off: turn off annunciator 3.
+
+			This exists on both the II/II+ and the IIe, but has no effect on
+			video on the older machines. It's intended to be used on the IIe
+			to confirm double-high resolution mode but has side effects in
+			selecting mixed mode output and discarding high-resolution
+			delay bits.
+		*/
+		void set_annunciator_3(bool annunciator_3) {
+			external_.annunciator_3 = annunciator_3;
+			deferrer_.defer(delay_, [this, annunciator_3] {
+				internal_.annunciator_3 = annunciator_3;
+				did_set_alternative_character_set(annunciator_3);
+			});
+		}
+		bool get_annunciator_3() const {
+			return external_.annunciator_3;
+		}
+
+	protected:
+		GraphicsMode graphics_mode(int row) const {
+			if(
+				internal_.text ||
+				(internal_.mixed && row >= 160 && row < 192)
+			) return internal_.columns_80 ? GraphicsMode::DoubleText : GraphicsMode::Text;
+			if(internal_.high_resolution) {
+				return (internal_.annunciator_3 && internal_.columns_80) ? GraphicsMode::DoubleHighRes : GraphicsMode::HighRes;
+			} else {
+				if(internal_.columns_80) return GraphicsMode::DoubleLowRes;
+				if(internal_.annunciator_3) return GraphicsMode::FatLowRes;
+				return GraphicsMode::LowRes;
+			}
+		}
+
+		int video_page() const {
+			return (internal_.store_80 || !internal_.page2) ? 0 : 1;
+		}
+
+		uint16_t get_row_address(int row) const {
+			const int character_row = row >> 3;
+			const int pixel_row = row & 7;
+			const uint16_t row_address = uint16_t((character_row >> 3) * 40 + ((character_row&7) << 7));
+
+			const GraphicsMode pixel_mode = graphics_mode(row);
+			return ((pixel_mode == GraphicsMode::HighRes) || (pixel_mode == GraphicsMode::DoubleHighRes)) ?
+				uint16_t(((video_page()+1) * 0x2000) + row_address + ((pixel_row&7) << 10)) :
+				uint16_t(((video_page()+1) * 0x400) + row_address);
+		}
+
+		virtual void did_set_annunciator_3(bool) = 0;
+		virtual void did_set_alternative_character_set(bool) = 0;
+
+	private:
+		// Maintain a DeferredQueue for delayed mode switches.
+		const TimeUnit delay_;
+		DeferredQueuePerformer<TimeUnit> deferrer_;
+
+		struct Switches {
+			bool alternative_character_set = false;
+			bool columns_80 = false;
+			bool store_80 = false;
+			bool page2 = false;
+			bool text = true;
+			bool mixed = false;
+			bool high_resolution = false;
+			bool annunciator_3 = false;
+		} external_, internal_;
+};
+
+}
+}
+
+#endif /* VideoSwitches_h */

OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj

@@ -1315,6 +1315,7 @@
 		4B8DF4D62546561300F3433C /* MemoryMap.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MemoryMap.hpp; sourceTree = "<group>"; };
 		4B8DF4D725465B7500F3433C /* IIgsMemoryMapTests.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = IIgsMemoryMapTests.mm; sourceTree = "<group>"; };
 		4B8DF4ED254B840B00F3433C /* AppleClock.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = AppleClock.hpp; sourceTree = "<group>"; };
+		4B8DF4F2254E141700F3433C /* VideoSwitches.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = VideoSwitches.hpp; sourceTree = "<group>"; };
 		4B8E4ECD1DCE483D003716C3 /* KeyboardMachine.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = KeyboardMachine.hpp; sourceTree = "<group>"; };
 		4B8EF6071FE5AF830076CCDD /* LowpassSpeaker.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = LowpassSpeaker.hpp; sourceTree = "<group>"; };
 		4B8FE2141DA19D5F0090D3CE /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = Base; path = "Clock Signal/Base.lproj/Atari2600Options.xib"; sourceTree = SOURCE_ROOT; };
@@ -3761,6 +3762,7 @@
 				4BCE004C227CE8CA000CA200 /* DiskIICard.hpp */,
 				4BF40A5525424C770033EA39 /* LanguageCardSwitches.hpp */,
 				4BCE004F227CE8CA000CA200 /* Video.hpp */,
+				4B8DF4F2254E141700F3433C /* VideoSwitches.hpp */,
 			);
 			path = AppleII;
 			sourceTree = "<group>";