Represents a VDP display mode. More...

#include <DisplayMode.hh>

Public Types
enum	{ GRAPHIC1 = 0x00 , TEXT1 = 0x01 , MULTICOLOR = 0x02 , GRAPHIC2 = 0x04 , TEXT1Q = 0x05 , MULTIQ = 0x06 , GRAPHIC3 = 0x08 , TEXT2 = 0x09 , GRAPHIC4 = 0x0C , GRAPHIC5 = 0x10 , GRAPHIC6 = 0x14 , GRAPHIC7 = 0x1C }

Public Member Functions
constexpr	DisplayMode ()=default
	Create the initial display mode. More...

constexpr	DisplayMode (byte reg0, byte reg1, byte reg25)
	Create a specific display mode. More...

constexpr DisplayMode	updateReg25 (byte reg25) const

constexpr void	reset ()
	Bring the display mode to its initial state. More...

constexpr bool	operator== (const DisplayMode &) const =default
	Equals operator. More...

constexpr byte	getByte () const
	Get the display mode as a byte: YAE YJK M5..M1 combined. More...

constexpr void	setByte (byte mode_)
	Used for de-serialization. More...

constexpr byte	getBase () const
	Get the base display mode as an integer: M5..M1 combined. More...

constexpr bool	isV9938Mode () const
	Was this mode introduced by the V9938? More...

constexpr bool	isTextMode () const
	Is the current mode a text mode? Text1 and Text2 are text modes. More...

constexpr bool	isBitmapMode () const
	Is the current mode a bitmap mode? Graphic4 and higher are bitmap modes. More...

constexpr bool	isPlanar () const
	Is VRAM "planar" in the current display mode? Graphic 6 and 7 spread their bytes over two VRAM ICs, such that the even bytes go to the first half of the address space and the odd bytes to the second half. More...

constexpr bool	isSpriteNarrow () const
	Are sprite pixels narrow? More...

constexpr int	getSpriteMode (bool isMSX1) const
	Get the sprite mode of this display mode. More...

constexpr unsigned	getLineWidth () const
	Get number of pixels on a display line in this mode. More...

Static Public Attributes
static constexpr byte	REG0_MASK = 0x0E
	Bits of VDP register 0 that encode part of the display mode. More...

static constexpr byte	REG1_MASK = 0x18
	Bits of VDP register 1 that encode part of the display mode. More...

static constexpr byte	REG25_MASK = 0x18
	Bits of VDP register 25 that encode part of the display mode. More...

static constexpr byte	YJK = 0x20
	Encoding of YJK flag. More...

static constexpr byte	YAE = 0x40
	Encoding of YAE flag. More...

Detailed Description

Represents a VDP display mode.

A display mode determines how bytes in the VRAM are converted to pixel colors. A display mode consists of a base mode with YJK filters on top. Only the V9958 supports YJK filters.

Definition at line 15 of file DisplayMode.hh.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

Enumerator
GRAPHIC1
TEXT1
MULTICOLOR
GRAPHIC2
TEXT1Q
MULTIQ
GRAPHIC3
TEXT2
GRAPHIC4
GRAPHIC5
GRAPHIC6
GRAPHIC7

Definition at line 26 of file DisplayMode.hh.

Constructor & Destructor Documentation

◆ DisplayMode() [1/2]

constexpr openmsx::DisplayMode::DisplayMode ( )

constexprdefault

Create the initial display mode.

Referenced by reset(), and updateReg25().

◆ DisplayMode() [2/2]

constexpr openmsx::DisplayMode::DisplayMode	(	byte	reg0,
		byte	reg1,
		byte	reg25
	)

inlineconstexpr

Create a specific display mode.

Parameters

reg0	The contents of VDP register 0.
reg1	The contents of VDP register 1.
reg25	The contents of VDP register 25; on non-V9958 chips, pass 0.

Definition at line 66 of file DisplayMode.hh.

Member Function Documentation

◆ getBase()

constexpr byte openmsx::DisplayMode::getBase ( ) const

inlineconstexpr

Get the base display mode as an integer: M5..M1 combined.

If YJK is active, the base mode is the underlying display mode.

Returns: The integer representation of the base of this display mode, in the range [0..0x1F].

Definition at line 108 of file DisplayMode.hh.

Referenced by getSpriteMode(), isBitmapMode(), isTextMode(), openmsx::CharacterConverter< Pixel >::setDisplayMode(), openmsx::VDPCmdEngine::updateDisplayMode(), openmsx::PixelRenderer::updatePalette(), and updateReg25().

◆ getByte()

constexpr byte openmsx::DisplayMode::getByte ( ) const

inlineconstexpr

Get the display mode as a byte: YAE YJK M5..M1 combined.

Returns: The byte representation of this display mode, in the range [0..0x7F].

Definition at line 94 of file DisplayMode.hh.

Referenced by openmsx::VDP::getBackgroundColor(), openmsx::VDP::serialize(), openmsx::SDLRasterizer< Pixel >::setDisplayMode(), openmsx::PixelRenderer::updateDisplayMode(), and openmsx::PixelRenderer::updatePalette().

◆ getLineWidth()

constexpr unsigned openmsx::DisplayMode::getLineWidth ( ) const

inlineconstexpr

Get number of pixels on a display line in this mode.

Returns: 512 for Text 2, Graphic 5 and 6, 256 for all other modes. TODO: Would it make more sense to treat Text 2 as 480 pixels?

Definition at line 181 of file DisplayMode.hh.

References GRAPHIC5, GRAPHIC6, and TEXT2.

Referenced by openmsx::SDLRasterizer< Pixel >::drawDisplay().

◆ getSpriteMode()

constexpr int openmsx::DisplayMode::getSpriteMode ( bool isMSX1 ) const

inlineconstexpr

Get the sprite mode of this display mode.

Returns: The current sprite mode: 0 means no sprites, 1 means sprite mode 1 (MSX1 display modes), 2 means sprite mode 2 (MSX2 display modes).

Definition at line 159 of file DisplayMode.hh.

References getBase(), GRAPHIC1, GRAPHIC2, GRAPHIC3, GRAPHIC4, GRAPHIC5, GRAPHIC6, GRAPHIC7, MULTICOLOR, MULTIQ, TEXT1, TEXT1Q, and TEXT2.

Referenced by openmsx::VDP::spritesEnabled(), and openmsx::VDP::spritesEnabledFast().

◆ isBitmapMode()

constexpr bool openmsx::DisplayMode::isBitmapMode ( ) const

inlineconstexpr

Is the current mode a bitmap mode? Graphic4 and higher are bitmap modes.

Returns: True iff the current mode is a bitmap mode.

Definition at line 131 of file DisplayMode.hh.

References getBase().

Referenced by openmsx::SDLRasterizer< Pixel >::drawDisplay(), and openmsx::SDLRasterizer< Pixel >::setDisplayMode().

◆ isPlanar()

constexpr bool openmsx::DisplayMode::isPlanar ( ) const

inlineconstexpr

Is VRAM "planar" in the current display mode? Graphic 6 and 7 spread their bytes over two VRAM ICs, such that the even bytes go to the first half of the address space and the odd bytes to the second half.

Returns: True iff the current display mode has planar VRAM.

Definition at line 141 of file DisplayMode.hh.

Referenced by openmsx::SDLRasterizer< Pixel >::drawDisplay().

◆ isSpriteNarrow()

constexpr bool openmsx::DisplayMode::isSpriteNarrow ( ) const

inlineconstexpr

Are sprite pixels narrow?

Definition at line 148 of file DisplayMode.hh.

References GRAPHIC5.

◆ isTextMode()

constexpr bool openmsx::DisplayMode::isTextMode ( ) const

inlineconstexpr

Is the current mode a text mode? Text1 and Text2 are text modes.

Returns: True iff the current mode is a text mode.

Definition at line 123 of file DisplayMode.hh.

References getBase(), TEXT1, TEXT1Q, and TEXT2.

Referenced by openmsx::SDLRasterizer< Pixel >::drawDisplay(), openmsx::VDP::getLeftSprites(), and openmsx::VDP::getRightBorder().

◆ isV9938Mode()

constexpr bool openmsx::DisplayMode::isV9938Mode ( ) const

inlineconstexpr

Was this mode introduced by the V9938?

Returns: True iff the base of this mode only is available on V9938/58.

Definition at line 115 of file DisplayMode.hh.

◆ operator==()

constexpr bool openmsx::DisplayMode::operator== ( const DisplayMode & ) const

constexprdefault

Equals operator.

◆ reset()

constexpr void openmsx::DisplayMode::reset ( )

inlineconstexpr

Bring the display mode to its initial state.

Definition at line 82 of file DisplayMode.hh.

References DisplayMode().

◆ setByte()

constexpr void openmsx::DisplayMode::setByte ( byte mode_ )

inlineconstexpr

Used for de-serialization.

Definition at line 99 of file DisplayMode.hh.

Referenced by openmsx::VDP::serialize().

◆ updateReg25()

constexpr DisplayMode openmsx::DisplayMode::updateReg25 ( byte reg25 ) const

inlineconstexpr

Definition at line 75 of file DisplayMode.hh.

References DisplayMode(), and getBase().

Member Data Documentation

◆ REG0_MASK

constexpr byte openmsx::DisplayMode::REG0_MASK = 0x0E

staticconstexpr

Bits of VDP register 0 that encode part of the display mode.

Definition at line 42 of file DisplayMode.hh.

◆ REG1_MASK

constexpr byte openmsx::DisplayMode::REG1_MASK = 0x18

staticconstexpr

Bits of VDP register 1 that encode part of the display mode.

Definition at line 45 of file DisplayMode.hh.

◆ REG25_MASK

constexpr byte openmsx::DisplayMode::REG25_MASK = 0x18

staticconstexpr

Bits of VDP register 25 that encode part of the display mode.

Definition at line 48 of file DisplayMode.hh.

◆ YAE

constexpr byte openmsx::DisplayMode::YAE = 0x40

staticconstexpr

Encoding of YAE flag.

Definition at line 54 of file DisplayMode.hh.

Referenced by openmsx::BitmapConverter< Pixel >::convertLine(), and openmsx::BitmapConverter< Pixel >::convertLinePlanar().

◆ YJK

constexpr byte openmsx::DisplayMode::YJK = 0x20

staticconstexpr

Encoding of YJK flag.

Definition at line 51 of file DisplayMode.hh.

Referenced by openmsx::BitmapConverter< Pixel >::convertLine(), and openmsx::BitmapConverter< Pixel >::convertLinePlanar().

The documentation for this class was generated from the following file:

DisplayMode.hh

Public Types

Public Member Functions

Static Public Attributes

Detailed Description

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ DisplayMode() [1/2]

◆ DisplayMode() [2/2]

Member Function Documentation

◆ getBase()

◆ getByte()

◆ getLineWidth()

◆ getSpriteMode()

◆ isBitmapMode()

◆ isPlanar()

◆ isSpriteNarrow()

◆ isTextMode()

◆ isV9938Mode()

◆ operator==()

◆ reset()

◆ setByte()

◆ updateReg25()

Member Data Documentation

◆ REG0_MASK

◆ REG1_MASK

◆ REG25_MASK

◆ YAE

◆ YJK