Everything zoom_view_open needs; nothing it does not. More...

#include <zoom.h>

Collaboration diagram for zoom_view_cfg_t:

Data Fields
zoom_source_t	src
	Bound source (see zoom_source_init).
zoom_scratch_t	scratch
	Caller-owned composite buffers.
ra8_ui_rect_t	dst
	Viewport in framebuffer pixels.
uint8_t	scale
	Opening magnification (0 => scale_min).
uint8_t	scale_max
	Ladder ceiling (0 => k_zoom_scale_max).
zoom_policy_t	policy
	Waveform scheduling policy.
uint16_t	settle_ms
	Settle window (0 => the module default).
int32_t	focus_x
	Opening centre, source pixels (x).
int32_t	focus_y
	Opening centre, source pixels (y).

Detailed Description

Everything zoom_view_open needs; nothing it does not.

The focus fields are in source pixels and name the point the view opens centred on – the panel coordinate of the tap that opened the viewer, mapped back through whatever laid the image out. Zero/zero is the image's top-left corner, which after clamping is simply "top-left of the image", the natural place to open a comic page.

Invariant: dst.w > 0 and dst.h > 0.; scale lies in [k_zoom_scale_min, effective scale_max].

Example:: const zoom_view_cfg_t cfg = {

.src = src, .scratch = scratch,

.dst = { .x = 0, .y = 0, .w = 1024, .h = 552 },

.scale = k_zoom_scale_min, .scale_max = 4U,

.policy = k_zoom_policy_responsive,

.focus_x = (int32_t)tap_src_x, .focus_y = (int32_t)tap_src_y,

};

zoom_view_cfg_t
Everything zoom_view_open needs; nothing it does not.
Definition zoom.h:404

zoom_view_cfg_t::src
zoom_source_t src
Bound source (see zoom_source_init).
Definition zoom.h:405

zoom_view_cfg_t::focus_y
int32_t focus_y
Opening centre, source pixels (y).
Definition zoom.h:413

zoom_view_cfg_t::scratch
zoom_scratch_t scratch
Caller-owned composite buffers.
Definition zoom.h:406

k_zoom_policy_responsive
@ k_zoom_policy_responsive
Fast during a burst, quality once settled.
Definition zoom.h:204

k_zoom_scale_min
@ k_zoom_scale_min
1:1 – one source pixel per panel pixel.
Definition zoom.h:118