From 64a2de1986fd255c149bd1fec714aeb1c6edf0ba Mon Sep 17 00:00:00 2001
From: Ramakrishnan Muthukrishnan <ram@rkrishnan.org>
Date: Mon, 1 Jan 2024 22:54:42 +0530
Subject: [PATCH] ctune scrolling: leave a margin (5% of display width) on each
side
---
vfo.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/vfo.c b/vfo.c
index 25f1e49..8bf7c7f 100644
--- a/vfo.c
+++ b/vfo.c
@@ -727,15 +727,24 @@ void vfo_id_move(int id, long long hz, int round) {
log_trace("vfo_id_move: ctune, vfo changed");
// don't let ctun go beyond end of passband
long long frequency = vfo[id].frequency;
- long long rx_low =
- vfo[id].ctun_frequency + hz + active_receiver->filter_low;
- long long rx_high =
- vfo[id].ctun_frequency + hz + active_receiver->filter_high;
+
+ // XXX: this calculation completely ignores the "zoom"
+ // value and "pan" value.
long long half = (long long)active_receiver->sample_rate / 2LL;
long long min_freq = frequency - half;
long long max_freq = frequency + half;
- if (rx_low <= min_freq) {
+ long long display_width = max_freq - min_freq;
+ // display_margin is the margin from display edge to start
+ // scrolling - in fraction of display width
+ long long display_margin = 0.05;
+
+ long long rx_low =
+ vfo[id].ctun_frequency + hz + active_receiver->filter_low;
+ long long rx_high =
+ vfo[id].ctun_frequency + hz + active_receiver->filter_high;
+
+ if (rx_low <= (min_freq + (display_width * display_margin))) {
// XXX: move the background. how do we move the
// background? Set the freq to the new center freq?
// i.e. in ctun mode, vfo[id].ctune_frequency is the
@@ -750,7 +759,7 @@ void vfo_id_move(int id, long long hz, int round) {
receiver_frequency_changed(receiver[id]);
g_idle_add(ext_vfo_update, NULL);
return;
- } else if (rx_high >= max_freq) {
+ } else if (rx_high >= (max_freq - (display_width * display_margin))) {
// XXX: move the background
long long delta_move = rx_high - max_freq;
vfo[id].frequency = vfo[id].frequency + hz + delta_move;
--
2.45.2