fdl_framing.cpp File Reference

Framing-from-intent computation — aspect ratio fitting with protection. More...

#include "fdl_framing.h"
#include "fdl_constants.h"

Functions
fdl_from_intent_result_t	fdl::detail::compute_framing_from_intent (fdl_dimensions_f64_t canvas_dims, fdl_dimensions_f64_t working_dims, double squeeze, fdl_dimensions_i64_t aspect_ratio, double protection, fdl_round_strategy_t rounding)
	Compute a framing decision from a framing intent.

Detailed Description

Framing-from-intent computation — aspect ratio fitting with protection.

Algorithm:

1. Compare intent aspect ratio with working (effective or canvas) aspect ratio.
2. If intent is wider: letterbox (fit to width, shrink height). If intent is narrower: pillarbox (fit to height, shrink width).
3. If protection > 0, round to get protection dimensions, then shrink by the protection factor to get final framing dimensions.
4. Center both framing and protection anchors within the full canvas.

Function Documentation

compute_framing_from_intent()

fdl_from_intent_result_t fdl::detail::compute_framing_from_intent	(	fdl_dimensions_f64_t	canvas_dims,
		fdl_dimensions_f64_t	working_dims,
		double	squeeze,
		fdl_dimensions_i64_t	aspect_ratio,
		double	protection,
		fdl_round_strategy_t	rounding
	)

Compute a framing decision from a framing intent.

Returns a zeroed result if aspect_ratio.height or working_dims.height is zero (guards against division by zero).

Parameters

canvas_dims	Full canvas dimensions (for anchor centering).
working_dims	Effective dimensions if available, else canvas dims.
squeeze	Anamorphic squeeze factor.
aspect_ratio	Target aspect ratio as integer width:height (height must be > 0).
protection	Protection factor (0.0 for no protection).
rounding	Rounding strategy.

Returns

Computed framing dimensions, anchors, and optional protection.