nCine::DrawableNode class
#include <nCine/Graphics/DrawableNode.h>

Base class for scene nodes that can be drawn through the render queue.

Extends SceneNode with everything needed to issue a draw: a node area (width and height), an anchor point for its transform, blending state and a RenderCommand. On OnDraw the node updates its render command and submits it to the render queue. Concrete drawables (sprites, particles) derive from this class.

Base classes

class SceneNode: Base node of the scene graph transformation hierarchy.

Derived classes

class BaseSprite: Base class for textured sprites.

Public types

enum class BlendingPreset { DISABLED, ALPHA, PREMULTIPLIED_ALPHA, ADDITIVE, MULTIPLY }: Presets for source and destination blending factors.
enum class BlendingFactor { ZERO, ONE, SRC_COLOR, ONE_MINUS_SRC_COLOR, DST_COLOR, ONE_MINUS_DST_COLOR, SRC_ALPHA, ONE_MINUS_SRC_ALPHA, DST_ALPHA, ONE_MINUS_DST_ALPHA, CONSTANT_COLOR, ONE_MINUS_CONSTANT_COLOR, CONSTANT_ALPHA, ONE_MINUS_CONSTANT_ALPHA, SRC_ALPHA_SATURATE }: OpenGL blending factors.

Constructors, destructors, conversion operators

DrawableNode(SceneNode* parent, float xx, float yy): Creates a node as a child of parent at the relative position (xx, yy).
DrawableNode(SceneNode* parent, Vector2f position): Creates a node as a child of parent at the relative position position.
DrawableNode(SceneNode* parent) explicit: Creates a node as a child of parent, positioned at the relative origin.
DrawableNode(): Creates a node with no parent, positioned at the origin.
~DrawableNode() override
DrawableNode(DrawableNode&&)
DrawableNode(const DrawableNode& other) protected: Protected copy constructor used to clone objects.

Public functions

auto operator=(const DrawableNode&) -> DrawableNode& deleted
auto operator=(DrawableNode&&) -> DrawableNode&
auto OnDraw(RenderQueue& renderQueue) -> bool override: Called when the node needs to be drawn, returning true if a command was added.
auto width() const -> float virtual: Returns the width of the node area.
auto height() const -> float virtual: Returns the height of the node area.
auto size() const -> Vector2f: Returns the size of the node area.
auto absWidth() const -> float virtual: Returns the absolute width of the node area.
auto absHeight() const -> float virtual: Returns the absolute height of the node area.
auto absSize() const -> Vector2f: Returns the absolute size of the node area.
auto anchorPoint() const -> Vector2f: Returns the transformation anchor point.
void setAnchorPoint(float xx, float yy): Sets the transformation anchor point.
void setAnchorPoint(Vector2f point): Sets the transformation anchor point from a Vector2f.
auto isBlendingEnabled() const -> bool: Returns whether the node renders with blending enabled.
void setBlendingEnabled(bool blendingEnabled): Sets the blending state for node rendering.
auto srcBlendingFactor() const -> BlendingFactor: Returns the source blending factor.
auto destBlendingFactor() const -> BlendingFactor: Returns the destination blending factor.
void setBlendingPreset(BlendingPreset blendingPreset): Sets source and destination blending factors from a preset.
void setBlendingFactors(BlendingFactor srcBlendingFactor, BlendingFactor destBlendingFactor): Sets specific source and destination blending factors.
auto lastFrameRendered() const -> std::uint32_t: Returns the last frame in which any viewport rendered this node (i.e. it was not culled).
auto aabb() const -> Rectf: Returns the axis-aligned bounding box of the node area in the last frame.

Protected functions

void updateAabb() virtual: Recalculates the axis-aligned bounding box.
void updateCulling(): Called by each viewport update to refresh this node's culling state.
void shaderHasChanged() pure virtual: Performs the required tasks upon a change to the shader.
void updateRenderCommand() pure virtual: Updates the render command before the node is drawn.

Protected variables

float width_: Node width in pixels.
float height_: Node height in pixels.
RenderCommand renderCommand_: The render command associated with this node.
std::uint32_t lastFrameRendered_: The last frame in which any viewport rendered this node.
Rectf aabb_: Axis-aligned bounding box of the node area.

Constants

static const Vector2f AnchorCenter
static const Vector2f AnchorBottomLeft
static const Vector2f AnchorTopLeft
static const Vector2f AnchorBottomRight
static const Vector2f AnchorTopRight

Enum documentation

enum class nCine::DrawableNode::BlendingPreset

Presets for source and destination blending factors.

Enumerators
DISABLED	Uses `GL_ONE` and `GL_ZERO`
ALPHA	Uses `GL_SRC_ALPHA` and `GL_ONE_MINUS_SRC_ALPHA`
PREMULTIPLIED_ALPHA	Uses `GL_ONE` and `GL_ONE_MINUS_SRC_ALPHA`
ADDITIVE	Uses `GL_SRC_ALPHA` and `GL_ONE`
MULTIPLY	Uses `GL_DST_COLOR` and `GL_ZERO`

nCine::DrawableNode class #include <nCine/Graphics/DrawableNode.h>

Enum documentation

enum class nCine::DrawableNode::BlendingPreset

nCine::DrawableNode class
#include <nCine/Graphics/DrawableNode.h>