Programmer's Guide to PC & PS/2 Video Systems

Cover
Contents
Acknowledgments
Introduction
	What This Book Is About
	What You Need to Use This Book
		Languages
		Operating System
		Hardware
		Manuals
Special Offer
1 IBM Video Hardware and Firmware
	IBM PC and PS/2 Video Hardware
	IBM Monochrome Display Adapter and Color Graphics Adapter
	Hercules Graphics Card
	Hercules Graphics Card Plus
	IBM Enhanced Graphics Adapter
	Hercules InColor Card
	Multi-Color Graphics Array
	Video Graphics Array
	Introduction to the ROM BIOS Interface
		Interrupt 10H
		Video Display Data Area
		Accessing the Video BIOS from a High-Level Language
2 Programming the Hardware
	Functional Components of IBM PC and PS/2 Video Subsystems
		Monitor
		Video Buffer
		Color and Character Display Hardware
		CRT Controller
	The Display Refresh Cycle
		Horizontal Timing
		Vertical Timing
	Programming the CRT Controller
		MDA
		CGA
		Hercules Adapters
		EGA
		MCGA
		VGA
	Basic CRTC Computations
		Dot Clock
		Horizontal Timing
		Vertical Timing
	The CRT Status Register
	Video Modes
		Resolution
		Colors
		Video Buffer Organization
	Hardware Video Mode Control
		MDA
		CGA and MCGA
		HGC
		HGC+ and InColor Card
		EGA and VGA
			Sequencer
			Graphics Controller
			Attribute Controller
		Video BIOS Support
	Combinations of Video Subsystems
		MDA
		Hercules
		CGA
		EGA
		MCGA
		VGA
3 Alphanumeric Modes
	Using Alphanumeric Modes
		BIOS and Operating-System Support
		Speed
		Compatibility
	Representation of Alphanumeric Data
	Attributes
		MDA
		HGC
		CGA
		EGA
		InColor Card
		MCGA 5
		VGA
	Gray-Scale Summing
	Border Color
		CGA
		EGA and VGA
	Avoiding CGA Snow
		Blanking the Display
		Using the Vertical Blanking Interval
		Using the Horizontal Blanking Interval
	Using All the Video Buffer
		CGA Video Pages
		EGA, MCGA, and VGA Video Pages
	Cursor Control
		Cursor Size on the MDA and CGA
		Cursor Location on the MDA and CGA
		MCGA Cursor Control
		EGA and VGA Cursor Control
		ROM BIOS Cursor Emulation
		An Invisible Cursor
4 Graphics Modes
	Using Graphics Modes
	Mapping Pixels to the Screen
		CGA
		HGC
		EGA
		Hercules InColor Card
		MCGA and VGA
	Pixel Coordinates
		Pixel Coordinate Scaling
		Aspect Ratio
	Pixel Display Attributes
		CGA
		HGC
		EGA
			CGA Emulation Modes
			16-Color Modes
			Monochrome Graphics
			Blinking
			Border Color
		Hercules InColor Card
		MCGA
			2-Color Graphics Modes
			4-Color Graphics Mode
			256-Color Graphics Mode
		VGA 11
5 Pixel Programming
	Bit-Plane Programming
		EGA and VGA
			Read mode 0
			Read mode 1
			Write mode 0
			Write mode 1
			Write mode 2
			Write mode 3
			Sequencer Map Mask
		InColor Card
			Write mode 0-3
			Read mode
	Reading a Pixel’s Value
		CGA
		HGC and HGC+
		EGA
		InColor Card
		MCGA
		VGA
	Setting a Pixel’s Value
		CGA
		HGC and HGC+
		EGA
			Write mode 0
			Write mode 2
		InColor Card
		MCGA
		VGA
	Filling the Video Buffer
		CGA
		HGC and HGC+
		EGA and VGA
		InColor Card
		MCGA
6 Lines
	An Efficient Line-drawing Algorithm
		Scan-converting a Straight Line
		Bresenham's Algorithm
	Optimization
		Efficient Pixel Addressing
		Performance Comparisons
		Special Cases
	PC and PS/2 Implementations
		Modular Routines
		Minimizing Video Buffer Accesses
		Efficient Address Calculations
		CGA
		HGC
		EGA
		MCGA
		VGA
		InColor Card
	Line Attributes
	Clipping
		Pixel-by-Pixel Clipping
		A Brute-Force Approach
		A Better Algorithm
7 Circles and Ellipses
	Circles and Pixel Scaling
	An Ellipse-drawing Algorithm
		Scan-converting an Ellipse
		An Incremental Algorithm
		A Typical Implementation
		Problems and Pitfalls
		Accuracy
	Optimization
	Clipping
	True Circles
8 Region Fill
	What Is a Region?
		Interior and Border Pixels
		Connectivity
	Simple Fills with Horizontal Lines
	Three Region Fill Algorithms
		Simple Recursive Fill
		Line-Adjacency Fill
		Border Fill
	Comparing the Algorithms
9 Graphics Text
	Character Definition Tables
		Video BIOS Support
			Default CGA Characters
			Default EGA, VGA, and MCGA Characters
		Creating a Character Definition Table
	Software Character Generators
		Video BIOS Support
		Pixel Handling
	Designing a Software Character Generator
		Horizontal Alignment
		Variable Character Sizes
		Clipping
		Character Orientation
		Cooperating with the Video BIOS
		More Power, More Complexity
	Implementing a Software Character Generator
		CGA
		HGC and HCG+
		MCGA
		EGA and VGA
		InColor Card
10 Alphanumeric Character Sets
	Character Definition Tables
		Alphanumeric Character Definitions in ROM
			200-Line Modes
			350-Line Modes
			400-Line Modes
		Alphanumeric Character Definitions in RAM
			EGA and VGA
			HGC+
			InColor Card
			MCGA
	Updating Character Generator RAM
		EGA and VGA
		HGC+
		InColor Card
		MCGA
	Using RAM-based Character Sets
		ASCII Character Sets
			EGA, VGA, and MCGA
			HGC+ and InColor Card
		Extended Character Sets
			EGA y VGA
			MCGA
			HGC+ and InColor Card
		Compatibility Problems with Extended Character Codes
	Changing the Displayed Character Matrix
		EGA
		VGA
		MCGA
		HGC+ and InColor Card
			Programming Examples
	Graphics Windows in Alphanumeric Modes
		HGC+ and InColor Card
		EGA and VGA
		MCGA
11 Bit Blocks and Animation
	Bit Block Move
		CGA and MCGA
		EGA and VGA
		HGC
		InColor Card
	Bitwise Pixel Operations
		XOR
		NOT
		AND
		OR
	Bit Block Tiling
	Animation
		XOR Animation
			Outlining
			Rubberbanding
			Bit Block Moves
			Problems with XOR Animation
		Overlapping Bit Block Moves
	A Graphics-Mode Cursor
		XOR
		Bit Block Move
12 Some Advanced Video Programming Techniques
	A Vertical Interrupt Handler
		EGA and VGA
		MCGA
	Panning on the EGA and VGA
		Positioning the Screen Window
		Panning
		Resizing the Video Buffer
	Bit-Plane Layering
	EGA and VGA Split Screen
	The Light Pen Interface
		Light Pen Position
		Light Pen Switch
		Determining Hercules Video Modes
13 Graphics Subroutines in High-Level Languages
	Linking Graphics Subroutines
		Subroutine Calls
			Microsoft C
			Microsoft FORTRAN
			Turbo Pascal
			BASIC
		Interrupts to a Memory-Resident Driver
		Inline Code
	Global Data Areas
	Layered Graphics Interfaces
		Direct Hardware Programming
		Extended BIOS Interface
		High-Level Interface
Appendix A: Video BIOS Summary
	Hardware Supported by ROM Video BIOS
		MDA and CGA
		EGA
		MCGA
		VGA
		VGA Adapter
	Interrupt 10H
	Video BIOS Data Areas
		Video Display Data Area
		Save Areas
		Video Parameter Table
		Parameter Save Area
		Alphanumeric Character Set Override
		Graphics Character Set Override
		Display Combination Code Table
		User Palette Profile Table
		Video BIOS Save Area Programming
	Interrupt IDH Vector
	IBM PC and PS/2 Video BIOS Functions (INT 10H Interface)
		Function 0: Select Video Mode
		Function 1: Set Alphanumeric Cursor Size
		Function 2: Set Cursor Location
		Function 3: Return Cursor Status
		Function 4: Return Light Pen Position
		Function 5: Select Video Pages
		Function 6: Scroll Up
		Function 7: Scroll Down
		Function 8: Return Character Code and Attribute at Cursor
		Function 9: Write Character and Attribute at Cursor
		Function 0AH: Write Character(s) at Cursor Position
		Function 0BH: Set Overscan Color, Select 4-Color Palette
		Function 0CH: Store Pixel Value
		Function 0DH: Return Pixel Value
		Function 0EH: Display Character in Teletype Mode
		Function 0FH: Return Current Status
		Function 10H: Set Palette Registers, Set Intensity/Blink Attribute
		Function 11H: Character Generator Interface
		Function 12H: Video Subsystem Configuration (Alternate select)
		Function 13H: Display Character String
		Function 14H: (PC Convertible only)
		Function 15H: (PC Convertible only)
		Function 16H: (Reserved)
		Function 17H: (Reserved)
		Function 18H: (Reserved)
		Function 19H: (Reserved)
		Function 1AH: Video Display Combination
		Function 1BH: Video BIOS Functionality/State Information
		Function 1CH: Save or Restore Video State
Appendix B: Printing the Screen
	Alphanumeric Modes
		EGA, MCGA, VGA
		Block Graphics Characters
	Graphics Modes
	Graphics
		Writings a Screen Dump Routines
		RAM-Based Alphanumeric Character Definitions
Appendix C: Identifying Video Subsystems
	CGA and Clones
	Other Video Adapters
	PS/2s
Glossary
Index