canvas

type Canvas interface {

	// Save pushes the current graphics state (color, transform, clip) onto a stack.
	Save()
	// Restore pops the graphics state stack.
	Restore()

	// Translate shifts the origin by (dx, dy).
	Translate(dx, dy float64)
	// Rotate applies a rotation of angle radians around the current origin.
	Rotate(angle float64)
	// ScaleXY applies a non-uniform scale.
	ScaleXY(sx, sy float64)

	// MoveTo starts a new sub-path at (x, y).
	MoveTo(x, y float64)
	// LineTo adds a line segment from the current point to (x, y).
	LineTo(x, y float64)
	// QuadraticTo adds a quadratic Bézier curve to (x, y) via control point (cx, cy).
	QuadraticTo(cx, cy, x, y float64)
	// CubicTo adds a cubic Bézier curve to (x, y) via control points (cx1, cy1) and (cx2, cy2).
	CubicTo(cx1, cy1, cx2, cy2, x, y float64)
	// ClosePath closes the current sub-path with a line to the start point.
	ClosePath()
	// ClearPath discards the current path without drawing.
	ClearPath()

	// SetColor sets the current drawing color for both fill and stroke.
	SetColor(c color.Color)
	// SetRGBA sets the current drawing color from normalized components.
	SetRGBA(r, g, b, a float64)
	// SetLineWidth sets the stroke width in pixels.
	SetLineWidth(w float64)
	// SetLineDash sets the dash pattern. Pass nil or empty for solid lines.
	SetLineDash(pattern ...float64)
	// Fill fills the current path with the current color, then clears the path.
	Fill()
	// Stroke draws the current path outline, then clears the path.
	Stroke()
	// FillPreserve fills without clearing the path (allows subsequent stroke).
	FillPreserve()
	// Clip clips rendering to the current path. Call after constructing a path
	// (e.g. DrawRectangle). Use Save/Restore to undo the clip.
	Clip()

	// DrawCircle adds a circle path centered at (cx, cy) with radius r.
	DrawCircle(cx, cy, r float64)
	// DrawRectangle adds a rectangle path at (x, y) with dimensions (w, h).
	DrawRectangle(x, y, w, h float64)
	// DrawLine adds a line path from (x1, y1) to (x2, y2).
	DrawLine(x1, y1, x2, y2 float64)
	// DrawShape adds a path for the specified shape centered at (cx, cy) with size/radius r.
	// Supported shapes: "circle", "square", "triangle", "diamond", "triangleDown",
	// "plus", "cross", "star", "pentagon", "hexagon".
	DrawShape(shape string, cx, cy, r float64)

	// SetFontSize sets the font size in points.
	SetFontSize(size float64)
	// SetTabularNums enables or disables tabular (monospaced) digit widths
	// for subsequent text rendering. When enabled, digits occupy uniform
	// horizontal space for aligned numeric columns (e.g., axis tick labels).
	// Backends that don't support OpenType features may ignore this.
	SetTabularNums(enabled bool)
	// DrawStringAnchored draws text at (x, y) with anchor (ax, ay) ∈ [0,1].
	// (0,0) = top-left, (0.5,0.5) = center, (1,1) = bottom-right.
	DrawStringAnchored(text string, x, y, ax, ay float64)
	// MeasureString returns the width and height of the rendered text.
	MeasureString(text string) (w, h float64)

	// Clear fills the entire canvas with the given color.
	Clear(c color.Color)
	// Width returns the canvas width in pixels.
	Width() int
	// Height returns the canvas height in pixels.
	Height() int
	// DrawImage composites the given image onto the canvas at position (x, y).
	// Used for compositing panel sub-canvases during parallel rendering.
	DrawImage(img image.Image, x, y float64)

	// Close releases backend resources (GPU buffers, etc.).
	// Implementations that hold no resources may return nil.
	Close() error
}

type FontWeight int

type GGCanvas struct {
	// contains filtered or unexported fields
}

type RecordingCanvas struct {
	// contains filtered or unexported fields
}

type TextAnchor struct {
	X, Y float64 // [0,1] where (0,0) = top-left, (1,1) = bottom-right
}