From: Matthew Mondor <mmondor@pulsar-zone.net>
Date: Tue, 18 Apr 2023 00:14:38 +0000 (+0000)
Subject: - Performance improvement, disabling a full forced refresh per frame.
X-Git-Url: http://git.pulsar-zone.net/?a=commitdiff_plain;h=ad8428115ffd641e1e37908f5bafb6964422babd;p=ninvaders.git

- Performance improvement, disabling a full forced refresh per frame.
- Addition of the -f command line option to lower the FPS if needed.
---

diff --git a/MATT-README.txt b/MATT-README.txt
index 5d37d87..7ef88be 100644
--- a/MATT-README.txt
+++ b/MATT-README.txt
@@ -10,6 +10,9 @@ BUG FIXES
   64-bit.  Fixed.
 - Memory was leaked everytime the title screen was displayed in the
   form of unnecessarily created pads that were never deleted.
+- The refresh function forced a full screen refresh everytime,
+  making user input unresponsive whenever a terminal was slightly
+  restricted in bandwidth.
 
 
 IMPROVEMENTS
@@ -27,6 +30,9 @@ IMPROVEMENTS
 
 - Add high score keeping and display the scores on the title screen.
 
+- Bandwidth efficiency improvent and addition of the -f option to
+  lower the frame rate from the default (very high) 50, if necessary.
+
 
 TODO
 
diff --git a/globals.c b/globals.c
index c1e6026..aadc608 100644
--- a/globals.c
+++ b/globals.c
@@ -68,11 +68,15 @@ void showVersion(void)
 void showUsage(void)
 {
 
-	fprintf(stderr, "\n\nUsage: nInvaders [-l skill] [-L]\n");
-	fprintf(stderr, "   where -l 0=NIGHTMARE\n");
-	fprintf(stderr, "         -l 1=okay\n");
-	fprintf(stderr, "         -l 9=May I play daddy?!\n");
-	fprintf(stderr, "\n         -L display the distribution license\n");
+	fprintf(stderr, "\n\nUsage: nInvaders [-f <fps>] [-l skill] [-L]\n");
+	fprintf(stderr,
+		" Where:\n\n"
+		" -f <fps> - Frame rate, lower if unresponsive on low bps\n\n"
+		" -l 0=NIGHTMARE\n"
+		" -l 1=okay\n"
+		" -l 9=May I play daddy?!\n\n"
+		" -L display the distribution license\n");
+	fprintf(stderr, "\n");
 }
 
 
diff --git a/nInvaders.c b/nInvaders.c
index a24e8bb..b2f4e0c 100644
--- a/nInvaders.c
+++ b/nInvaders.c
@@ -33,7 +33,9 @@
 #include "aliens.h"
 #include "ufo.h"
 
-#define FPS 50
+#define DEFAULT_FPS 50
+
+int fps = DEFAULT_FPS;
 
 int lives;
 long score = 0, hiscore = 0;
@@ -73,8 +75,12 @@ static void evaluateCommandLine(int argc, char **argv)
 {
 	int ch, i;
 
-	while ((ch = getopt(argc, argv, "?l:L")) != -1) {
+	while ((ch = getopt(argc, argv, "?f:l:L")) != -1) {
 		switch (ch) {
+		case 'f':
+			if ((i = atoi(optarg)) >= 5 && i <= 50)
+				fps = i;
+			break;
 		case 'l':
 			if ((i = atoi(optarg)) > -1 && i < 10)
 				skill_level = i;
@@ -335,9 +341,9 @@ void setUpTimer(void)
 	struct itimerval myTimer;
 	struct sigaction myAction;
 	myTimer.it_value.tv_sec = 0;
-	myTimer.it_value.tv_usec = 1000000 / FPS;
+	myTimer.it_value.tv_usec = 1000000 / fps;
 	myTimer.it_interval.tv_sec = 0;
-	myTimer.it_interval.tv_usec = 1000000 / FPS;
+	myTimer.it_interval.tv_usec = 1000000 / fps;
 	setitimer(ITIMER_REAL, &myTimer, NULL);
 	
 	myAction.sa_handler = handleTimer;
diff --git a/view.c b/view.c
index c617c4d..d3add9e 100644
--- a/view.c
+++ b/view.c
@@ -594,9 +594,20 @@ void battleFieldClear(void)
  */
 void refreshScreen(void)
 {
-	redrawwin(wBattleField); // needed to display graphics properly at startup on some terminals
+	/*
+	 * The following is claimed to be necessary on some terminals for
+	 * graphics to properly display at startup.  It however is prohibitive
+	 * in that it forces a full refresh every FPS, which by default is 50.
+	 * For this reason, whenever a terminal is restricted in bandwidth,
+	 * even with speeds as high as 19200bps, it becomes completely
+	 * unresponsive to user input, even with the added -f option to lower
+	 * the FPS.  Without the following line, everything is fine.
+	 * If the issue was really at startup, it theoretically would be
+	 * possible to only force this refresh once or twice.  Disabled for
+	 * now.
+	 */
+	/* redrawwin(wBattleField); XXX */
 	wrefresh(wBattleField);
-
 }