RoomLayerManager - Manages layer visibility and compositing. More...

#include <room_layer_manager.h>

Public Member Functions
	RoomLayerManager ()

void	Reset ()

void	SetPriorityCompositing (bool enabled)

bool	IsPriorityCompositingEnabled () const

void	SetLayerVisible (LayerType layer, bool visible)

bool	IsLayerVisible (LayerType layer) const

void	SetLayerBlendMode (LayerType layer, LayerBlendMode mode)

LayerBlendMode	GetLayerBlendMode (LayerType layer) const

uint8_t	GetLayerAlpha (LayerType layer) const

void	SetObjectTranslucency (size_t object_index, bool translucent, uint8_t alpha=128)

bool	IsObjectTranslucent (size_t object_index) const

uint8_t	GetObjectAlpha (size_t object_index) const

void	ClearObjectTranslucency ()

void	SetBG2ColorMathEnabled (bool enabled)

bool	IsBG2ColorMathEnabled () const

void	SetBG2OnTop (bool on_top)

bool	IsBG2OnTop () const

void	ApplyLayerMerging (const LayerMergeType &merge_type)

void	ApplyLayerMergingPreserveVisibility (const LayerMergeType &merge_type)
	Apply layer merge settings without changing visibility.

bool	AreLayersMerged () const
	Check if layers are currently merged.

uint8_t	GetMergeTypeId () const
	Get the current merge type ID.

int	GetObjectLayerValue (int object_layer) const
	Get object layer value for buffer assignment.

int	CalculateObjectPriority (int object_layer) const

std::array< LayerType, 4 >	GetDrawOrder () const
	Get the draw order for layers.

void	ApplySurfaceColorMod (SDL_Surface *surface) const
	Apply surface color modulation for DarkRoom effect.

void	CompositeToOutput (Room &room, gfx::Bitmap &output) const
	Composite all visible layers into a single output bitmap.

Static Public Member Functions
static bool	IsObjectOnBG2 (int object_layer)
	Check if an object on a given layer should render to BG2.

static LayerType	GetObjectLayerType (int object_layer)
	Get the appropriate background layer type for an object.

static gfx::BackgroundBuffer &	GetLayerBuffer (Room &room, LayerType layer)
	Get the bitmap buffer for a layer type.

static const gfx::BackgroundBuffer &	GetLayerBuffer (const Room &room, LayerType layer)

static const char *	GetLayerName (LayerType layer)
	Get human-readable name for layer type.

static const char *	GetBlendModeName (LayerBlendMode mode)
	Get blend mode name.

Static Private Member Functions
static bool	IsTransparent (uint8_t pixel)
	Check if a pixel index represents transparency.

Private Attributes
std::array< bool, 4 >	layer_visible_

std::array< LayerBlendMode, 4 >	layer_blend_mode_

std::array< uint8_t, 4 >	layer_alpha_

std::vector< ObjectTranslucency >	object_translucency_

bool	bg2_on_top_ = false

bool	layers_merged_ = false

uint8_t	current_merge_type_id_ = 0

bool	use_priority_compositing_ = false

Detailed Description

RoomLayerManager - Manages layer visibility and compositing.

This class provides:

4-way layer visibility (BG1_Layout, BG1_Objects, BG2_Layout, BG2_Objects)
Layer blend mode control
Per-object translucency settings
Compositing layers to a final output bitmap

Usage: RoomLayerManager manager; manager.SetLayerVisible(LayerType::BG1_Objects, false); // Hide objects manager.SetLayerBlendMode(LayerType::BG2_Layout, LayerBlendMode::Translucent); manager.CompositeToOutput(room, output_bitmap);

Definition at line 79 of file room_layer_manager.h.

Constructor & Destructor Documentation

◆ RoomLayerManager()

yaze::zelda3::RoomLayerManager::RoomLayerManager ( )

inline

Definition at line 81 of file room_layer_manager.h.

References Reset().

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Member Function Documentation

◆ Reset()

void yaze::zelda3::RoomLayerManager::Reset ( )

inline

Definition at line 84 of file room_layer_manager.h.

References bg2_on_top_, current_merge_type_id_, layer_alpha_, layer_blend_mode_, layer_visible_, layers_merged_, yaze::zelda3::Normal, object_translucency_, and use_priority_compositing_.

Referenced by RoomLayerManager().

◆ SetPriorityCompositing()

void yaze::zelda3::RoomLayerManager::SetPriorityCompositing ( bool enabled )

inline

Definition at line 100 of file room_layer_manager.h.

References use_priority_compositing_.

◆ IsPriorityCompositingEnabled()

bool yaze::zelda3::RoomLayerManager::IsPriorityCompositingEnabled ( ) const

inline

Definition at line 101 of file room_layer_manager.h.

References use_priority_compositing_.

◆ SetLayerVisible()

void yaze::zelda3::RoomLayerManager::SetLayerVisible	(	LayerType	layer,
		bool	visible )

inline

Definition at line 104 of file room_layer_manager.h.

References layer_visible_.

Referenced by ApplyLayerMergingPreserveVisibility(), and yaze::editor::DungeonCanvasViewer::SetLayerVisible().

◆ IsLayerVisible()

bool yaze::zelda3::RoomLayerManager::IsLayerVisible ( LayerType layer ) const

inline

Definition at line 108 of file room_layer_manager.h.

References layer_visible_.

Referenced by ApplyLayerMergingPreserveVisibility(), and CompositeToOutput().

◆ SetLayerBlendMode()

void yaze::zelda3::RoomLayerManager::SetLayerBlendMode	(	LayerType	layer,
		LayerBlendMode	mode )

inline

Definition at line 113 of file room_layer_manager.h.

References yaze::zelda3::Addition, yaze::zelda3::Dark, layer_alpha_, layer_blend_mode_, yaze::zelda3::Normal, yaze::zelda3::Off, and yaze::zelda3::Translucent.

Referenced by ApplyLayerMerging(), and yaze::editor::DungeonCanvasViewer::SetLayerBlendMode().

◆ GetLayerBlendMode()

LayerBlendMode yaze::zelda3::RoomLayerManager::GetLayerBlendMode ( LayerType layer ) const

inline

Definition at line 135 of file room_layer_manager.h.

References layer_blend_mode_.

Referenced by CompositeToOutput().

◆ GetLayerAlpha()

uint8_t yaze::zelda3::RoomLayerManager::GetLayerAlpha ( LayerType layer ) const

inline

Definition at line 139 of file room_layer_manager.h.

References layer_alpha_.

Referenced by CompositeToOutput().

◆ SetObjectTranslucency()

void yaze::zelda3::RoomLayerManager::SetObjectTranslucency	(	size_t	object_index,
		bool	translucent,
		uint8_t	alpha = 128 )

inline

Definition at line 144 of file room_layer_manager.h.

References object_translucency_.

Referenced by yaze::editor::DungeonCanvasViewer::SetObjectTranslucent().

◆ IsObjectTranslucent()

bool yaze::zelda3::RoomLayerManager::IsObjectTranslucent ( size_t object_index ) const

inline

Definition at line 157 of file room_layer_manager.h.

References object_translucency_.

◆ GetObjectAlpha()

uint8_t yaze::zelda3::RoomLayerManager::GetObjectAlpha ( size_t object_index ) const

inline

Definition at line 166 of file room_layer_manager.h.

References object_translucency_.

◆ ClearObjectTranslucency()

void yaze::zelda3::RoomLayerManager::ClearObjectTranslucency ( )

inline

Definition at line 175 of file room_layer_manager.h.

References object_translucency_.

◆ SetBG2ColorMathEnabled()

void yaze::zelda3::RoomLayerManager::SetBG2ColorMathEnabled ( bool enabled )

inline

Definition at line 181 of file room_layer_manager.h.

References bg2_on_top_.

Referenced by ApplyLayerMerging().

◆ IsBG2ColorMathEnabled()

bool yaze::zelda3::RoomLayerManager::IsBG2ColorMathEnabled ( ) const

inline

Definition at line 182 of file room_layer_manager.h.

References bg2_on_top_.

◆ SetBG2OnTop()

void yaze::zelda3::RoomLayerManager::SetBG2OnTop ( bool on_top )

inline

Definition at line 185 of file room_layer_manager.h.

References bg2_on_top_.

◆ IsBG2OnTop()

bool yaze::zelda3::RoomLayerManager::IsBG2OnTop ( ) const

inline

Definition at line 186 of file room_layer_manager.h.

References bg2_on_top_.

◆ ApplyLayerMerging()

void yaze::zelda3::RoomLayerManager::ApplyLayerMerging ( const LayerMergeType & merge_type )

inline

Definition at line 192 of file room_layer_manager.h.

References yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::BG2_Layout, yaze::zelda3::BG2_Objects, current_merge_type_id_, yaze::zelda3::Dark, yaze::zelda3::LayerMergeType::ID, yaze::zelda3::LayerMergeType::Layer2OnTop, yaze::zelda3::LayerMergeType::Layer2Translucent, layers_merged_, yaze::zelda3::Normal, SetBG2ColorMathEnabled(), SetLayerBlendMode(), and yaze::zelda3::Translucent.

Referenced by ApplyLayerMergingPreserveVisibility().

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◆ ApplyLayerMergingPreserveVisibility()

void yaze::zelda3::RoomLayerManager::ApplyLayerMergingPreserveVisibility ( const LayerMergeType & merge_type )

inline

Apply layer merge settings without changing visibility.

Use this when you want to update blend/ordering from ROM data but preserve the user's manual visibility overrides.

Definition at line 230 of file room_layer_manager.h.

References ApplyLayerMerging(), yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::BG2_Layout, yaze::zelda3::BG2_Objects, IsLayerVisible(), and SetLayerVisible().

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◆ AreLayersMerged()

bool yaze::zelda3::RoomLayerManager::AreLayersMerged ( ) const

inline

Check if layers are currently merged.

Returns: true if any layer merging is active

Definition at line 251 of file room_layer_manager.h.

References layers_merged_.

◆ GetMergeTypeId()

uint8_t yaze::zelda3::RoomLayerManager::GetMergeTypeId ( ) const

inline

Get the current merge type ID.

Returns: The LayerMergeType ID (0-8)

Definition at line 257 of file room_layer_manager.h.

References current_merge_type_id_.

◆ GetObjectLayerValue()

int yaze::zelda3::RoomLayerManager::GetObjectLayerValue ( int object_layer ) const

inline

Get object layer value for buffer assignment.

Objects are assigned to buffers based on their layer value:

Layer 0: BG1 buffer (main floor/walls)
Layer 1: BG2 buffer (background details)
Layer 2: BG1 buffer with priority (overlays on BG1)

NOTE: Visual Z-order is fixed by SNES Mode 1 hardware (BG1 > BG2). This layer value only determines which buffer the object draws to, not the visual stacking order.

Parameters

object_layer The object's layer value (0, 1, 2)

Returns: Layer value (same as input - used for buffer routing)

Definition at line 278 of file room_layer_manager.h.

◆ CalculateObjectPriority()

int yaze::zelda3::RoomLayerManager::CalculateObjectPriority ( int object_layer ) const

inline

Definition at line 284 of file room_layer_manager.h.

◆ IsObjectOnBG2()

static bool yaze::zelda3::RoomLayerManager::IsObjectOnBG2 ( int object_layer )

inlinestatic

Check if an object on a given layer should render to BG2.

Parameters

object_layer The object's layer value

Returns: true if object renders to BG2 buffer

Definition at line 293 of file room_layer_manager.h.

Referenced by GetObjectLayerType().

◆ GetObjectLayerType()

static LayerType yaze::zelda3::RoomLayerManager::GetObjectLayerType ( int object_layer )

inlinestatic

Get the appropriate background layer type for an object.

Parameters

object_layer The object's layer value (0, 1, 2)

Returns: The LayerType for this object's background

Definition at line 303 of file room_layer_manager.h.

References yaze::zelda3::BG1_Objects, yaze::zelda3::BG2_Objects, and IsObjectOnBG2().

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◆ GetDrawOrder()

std::array< LayerType, 4 > yaze::zelda3::RoomLayerManager::GetDrawOrder ( ) const

inline

Get the draw order for layers.

Returns layers in the order they should be drawn (back to front).

SNES Mode 1 default priority: BG1 > BG2 (BG1 on top) The "Layer2OnTop" flag from ROM controls COLOR MATH effects (sub-screen participation for transparency/additive blend), NOT the actual Z-order of opaque pixels.

Draw order is ALWAYS: BG2 (back) -> BG1 (front) Blend modes handle the visual effects separately.

Definition at line 321 of file room_layer_manager.h.

References yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::BG2_Layout, and yaze::zelda3::BG2_Objects.

◆ GetLayerBuffer() [1/2]

static gfx::BackgroundBuffer & yaze::zelda3::RoomLayerManager::GetLayerBuffer	(	Room &	room,
		LayerType	layer )

inlinestatic

Get the bitmap buffer for a layer type.

Definition at line 331 of file room_layer_manager.h.

References yaze::zelda3::Room::bg1_buffer(), yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::Room::bg2_buffer(), yaze::zelda3::BG2_Layout, yaze::zelda3::BG2_Objects, yaze::zelda3::Room::object_bg1_buffer(), and yaze::zelda3::Room::object_bg2_buffer().

Referenced by CompositeToOutput().

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◆ GetLayerBuffer() [2/2]

static const gfx::BackgroundBuffer & yaze::zelda3::RoomLayerManager::GetLayerBuffer	(	const Room &	room,
		LayerType	layer )

inlinestatic

Definition at line 346 of file room_layer_manager.h.

References yaze::zelda3::Room::bg1_buffer(), yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::Room::bg2_buffer(), yaze::zelda3::BG2_Layout, yaze::zelda3::BG2_Objects, yaze::zelda3::Room::object_bg1_buffer(), and yaze::zelda3::Room::object_bg2_buffer().

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◆ GetLayerName()

static const char * yaze::zelda3::RoomLayerManager::GetLayerName ( LayerType layer )

inlinestatic

Get human-readable name for layer type.

Definition at line 365 of file room_layer_manager.h.

References yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::BG2_Layout, and yaze::zelda3::BG2_Objects.

◆ GetBlendModeName()

static const char * yaze::zelda3::RoomLayerManager::GetBlendModeName ( LayerBlendMode mode )

inlinestatic

Get blend mode name.

Definition at line 382 of file room_layer_manager.h.

References yaze::zelda3::Addition, yaze::zelda3::Dark, yaze::zelda3::Normal, yaze::zelda3::Off, and yaze::zelda3::Translucent.

◆ ApplySurfaceColorMod()

void yaze::zelda3::RoomLayerManager::ApplySurfaceColorMod ( SDL_Surface * surface ) const

inline

Apply surface color modulation for DarkRoom effect.

In DarkRoom mode (merge type 0x08), surfaces should be darkened to 50%. This should be called before drawing each layer in separate mode to match the composite mode appearance.

Parameters

surface The SDL surface to apply modulation to

Definition at line 407 of file room_layer_manager.h.

References current_merge_type_id_.

◆ CompositeToOutput()

void yaze::zelda3::RoomLayerManager::CompositeToOutput	(	Room &	room,
		gfx::Bitmap &	output ) const

Composite all visible layers into a single output bitmap.

Implements SNES Mode 1 per-tile priority compositing. Each tile's priority bit affects its effective Z-order:

Layer	Priority	Effective Order
BG1	0	0 (back)
BG2	0	1
BG2	1	2
BG1	1	3 (front)

This allows BG2 tiles with priority 1 to appear above BG1 tiles with priority 0, matching authentic SNES hardware behavior.

Applies per-layer visibility and blend modes at pixel level. Transparency is detected via palette index 255 (object buffer fill color).

Note: PALETTE HANDLING: Room layer buffers have their palettes applied via SetPalette(vector<SDL_Color>), which means their internal SnesPalette (accessible via bitmap.palette()) is EMPTY. This method extracts the palette directly from the first visible layer's SDL surface and applies it to the output bitmap. See the "Bitmap Dual Palette System" section in docs/public/developer/palette-system-overview.md for details.

Parameters

room	The room containing the layer buffers
output	Output bitmap to receive composited result (512x512)

See also: ApplySDLPaletteToBitmap() for the palette extraction implementation; docs/internal/agents/composite-layer-system.md for full documentation

Definition at line 46 of file room_layer_manager.cc.

References yaze::zelda3::Addition, yaze::zelda3::Room::bg1_buffer(), yaze::zelda3::BG1_Layout, yaze::zelda3::BG1_Objects, yaze::zelda3::BG2_Layout, yaze::zelda3::BG2_Objects, yaze::gfx::BackgroundBuffer::bitmap(), yaze::gfx::Bitmap::Create(), current_merge_type_id_, yaze::zelda3::Dark, yaze::gfx::Bitmap::Fill(), GetLayerAlpha(), GetLayerBlendMode(), GetLayerBuffer(), yaze::gfx::Bitmap::height(), IsLayerVisible(), IsTransparent(), yaze::gfx::Bitmap::mutable_data(), yaze::zelda3::Normal, yaze::zelda3::Off, yaze::gfx::Bitmap::set_modified(), yaze::gfx::Bitmap::surface(), yaze::zelda3::Translucent, yaze::gfx::Bitmap::UpdateSurfacePixels(), and yaze::gfx::Bitmap::width().

Referenced by yaze::zelda3::Room::GetCompositeBitmap().

◆ IsTransparent()

static bool yaze::zelda3::RoomLayerManager::IsTransparent ( uint8_t pixel )

inlinestaticprivate

Check if a pixel index represents transparency.

IMPORTANT: Only treat 255 as transparent (fill color for undrawn areas). Do NOT treat 0 as transparent! In dungeon rendering:

Source pixel 1 with palette_offset 0 writes final_color = 0 to the buffer
This represents palette[0] (actual color), NOT transparency
Buffers should be initialized to 255, not 0

Definition at line 467 of file room_layer_manager.h.

Referenced by CompositeToOutput().

Member Data Documentation

◆ layer_visible_

std::array<bool, 4> yaze::zelda3::RoomLayerManager::layer_visible_

private

Definition at line 471 of file room_layer_manager.h.

Referenced by IsLayerVisible(), Reset(), and SetLayerVisible().

◆ layer_blend_mode_

std::array<LayerBlendMode, 4> yaze::zelda3::RoomLayerManager::layer_blend_mode_

private

Definition at line 472 of file room_layer_manager.h.

Referenced by GetLayerBlendMode(), Reset(), and SetLayerBlendMode().

◆ layer_alpha_

std::array<uint8_t, 4> yaze::zelda3::RoomLayerManager::layer_alpha_

private

Definition at line 473 of file room_layer_manager.h.

Referenced by GetLayerAlpha(), Reset(), and SetLayerBlendMode().

◆ object_translucency_

std::vector<ObjectTranslucency> yaze::zelda3::RoomLayerManager::object_translucency_

private

Definition at line 474 of file room_layer_manager.h.

Referenced by ClearObjectTranslucency(), GetObjectAlpha(), IsObjectTranslucent(), Reset(), and SetObjectTranslucency().

◆ bg2_on_top_

bool yaze::zelda3::RoomLayerManager::bg2_on_top_ = false

private

Definition at line 479 of file room_layer_manager.h.

Referenced by IsBG2ColorMathEnabled(), IsBG2OnTop(), Reset(), SetBG2ColorMathEnabled(), and SetBG2OnTop().

◆ layers_merged_

bool yaze::zelda3::RoomLayerManager::layers_merged_ = false

private

Definition at line 482 of file room_layer_manager.h.

Referenced by ApplyLayerMerging(), AreLayersMerged(), and Reset().

◆ current_merge_type_id_

uint8_t yaze::zelda3::RoomLayerManager::current_merge_type_id_ = 0

private

Definition at line 483 of file room_layer_manager.h.

Referenced by ApplyLayerMerging(), ApplySurfaceColorMod(), CompositeToOutput(), GetMergeTypeId(), and Reset().

◆ use_priority_compositing_

bool yaze::zelda3::RoomLayerManager::use_priority_compositing_ = false

private

Definition at line 490 of file room_layer_manager.h.

Referenced by IsPriorityCompositingEnabled(), Reset(), and SetPriorityCompositing().

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

src/zelda3/dungeon/room_layer_manager.h
src/zelda3/dungeon/room_layer_manager.cc

	yaze 0.3.2 Link to the Past ROM Editor

Public Member Functions

Static Public Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ RoomLayerManager()

Member Function Documentation

◆ Reset()

◆ SetPriorityCompositing()

◆ IsPriorityCompositingEnabled()

◆ SetLayerVisible()

◆ IsLayerVisible()

◆ SetLayerBlendMode()

◆ GetLayerBlendMode()

◆ GetLayerAlpha()

◆ SetObjectTranslucency()

◆ IsObjectTranslucent()

◆ GetObjectAlpha()

◆ ClearObjectTranslucency()

◆ SetBG2ColorMathEnabled()

◆ IsBG2ColorMathEnabled()

◆ SetBG2OnTop()

◆ IsBG2OnTop()

◆ ApplyLayerMerging()

◆ ApplyLayerMergingPreserveVisibility()

◆ AreLayersMerged()

◆ GetMergeTypeId()

◆ GetObjectLayerValue()

◆ CalculateObjectPriority()

◆ IsObjectOnBG2()

◆ GetObjectLayerType()

◆ GetDrawOrder()

◆ GetLayerBuffer() [1/2]

◆ GetLayerBuffer() [2/2]

◆ GetLayerName()

◆ GetBlendModeName()

◆ ApplySurfaceColorMod()

◆ CompositeToOutput()

◆ IsTransparent()

Member Data Documentation

◆ layer_visible_

◆ layer_blend_mode_

◆ layer_alpha_

◆ object_translucency_

◆ bg2_on_top_

◆ layers_merged_

◆ current_merge_type_id_

◆ use_priority_compositing_