copy dirty lines to screen, add select() timeout & min time between draw() calls.

* add a timeout value (SELECT_TIMEOUT) of 20ms in the select() call
* wait at least 20ms (DRAW_TIMEOUT) between draw() calls
* only copy dirty lines from the buffer to the screen

what draw() does:
* clears dirty lines in the buffer
* draws the longest same-attributes string of each
  dirty line to the buffer with multiple xdraws() call
* copies the current dirty line from buffer to the screen with a single
  xcopy() call

this changeset makes st run ~10x faster.
This commit is contained in:
Aurélien Aptel 2012-01-21 23:14:41 +01:00
parent 13a8eeb810
commit 896310e592

47
st.c
View File

@ -13,8 +13,10 @@
#include <sys/ioctl.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
#include <X11/Xatom.h>
#include <X11/Xlib.h>
@ -22,9 +24,6 @@
#include <X11/cursorfont.h>
#include <X11/keysym.h>
#include <sys/time.h>
#include <time.h>
#if defined(__linux)
#include <pty.h>
#elif defined(__OpenBSD__) || defined(__NetBSD__) || defined(__APPLE__)
@ -50,6 +49,9 @@
#define XK_NO_MOD UINT_MAX
#define XK_ANY_MOD 0
#define SELECT_TIMEOUT (20*1000) /* 20 ms */
#define DRAW_TIMEOUT (20*1000) /* 20 ms */
#define SERRNO strerror(errno)
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define MAX(a, b) ((a) < (b) ? (b) : (a))
@ -138,6 +140,7 @@ typedef struct {
int ch; /* char height */
int cw; /* char width */
char state; /* focus, redraw, visible */
struct timeval lastdraw;
} XWindow;
typedef struct {
@ -179,6 +182,7 @@ static void drawregion(int, int, int, int);
static void execsh(void);
static void sigchld(int);
static void run(void);
static int last_draw_too_old(void);
static void csidump(void);
static void csihandle(void);
@ -214,6 +218,7 @@ static void ttywrite(const char *, size_t);
static void xdraws(char *, Glyph, int, int, int, int);
static void xhints(void);
static void xclear(int, int, int, int);
static void xcopy(int, int, int, int);
static void xdrawcursor(void);
static void xinit(void);
static void xloadcols(void);
@ -224,7 +229,7 @@ static void xresize(int, int);
static void expose(XEvent *);
static void visibility(XEvent *);
static void unmap(XEvent *);
static char* kmap(KeySym, unsigned int state);
static char* kmap(KeySym, unsigned int);
static void kpress(XEvent *);
static void cmessage(XEvent *);
static void resize(XEvent *);
@ -1786,6 +1791,14 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
XDrawLine(xw.dpy, xw.buf, dc.gc, winx, winy+1, winx+width-1, winy+1);
}
/* copy buffer pixmap to screen pixmap */
void
xcopy(int x, int y, int cols, int rows) {
int src_x = x*xw.cw, src_y = y*xw.ch, src_w = cols*xw.cw, src_h = rows*xw.ch;
int dst_x = BORDER+src_x, dst_y = BORDER+src_y;
XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, src_x, src_y, src_w, src_h, dst_x, dst_y);
}
void
xdrawcursor(void) {
static int oldx = 0;
@ -1806,6 +1819,8 @@ xdrawcursor(void) {
} else
xclear(oldx, oldy, oldx, oldy);
xcopy(oldx, oldy, 1, 1);
/* draw the new one */
if(!(term.c.state & CURSOR_HIDE) && (xw.state & WIN_FOCUSED)) {
sl = utf8size(g.c);
@ -1814,11 +1829,14 @@ xdrawcursor(void) {
xdraws(g.c, g, term.c.x, term.c.y, 1, sl);
oldx = term.c.x, oldy = term.c.y;
}
xcopy(term.c.x, term.c.y, 1, 1);
}
void
draw() {
drawregion(0, 0, term.col, term.row);
gettimeofday(&xw.lastdraw, NULL);
}
void
@ -1859,9 +1877,9 @@ drawregion(int x1, int y1, int x2, int y2) {
}
if(ib > 0)
xdraws(buf, base, ox, y, ic, ib);
xcopy(0, y, term.col, 1);
}
xdrawcursor();
XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, x1*xw.cw, y1*xw.ch, x2*xw.cw, y2*xw.ch, BORDER, BORDER);
}
void
@ -2006,25 +2024,42 @@ resize(XEvent *e) {
xresize(col, row);
}
int
last_draw_too_old(void) {
struct timeval now;
gettimeofday(&now, NULL);
return TIMEDIFF(now, xw.lastdraw) >= PRINT_TIMEOUT/1000;
}
void
run(void) {
XEvent ev;
fd_set rfd;
int xfd = XConnectionNumber(xw.dpy);
struct timeval timeout = {0};
int stuff_to_print = 0;
for(;;) {
FD_ZERO(&rfd);
FD_SET(cmdfd, &rfd);
FD_SET(xfd, &rfd);
if(select(MAX(xfd, cmdfd)+1, &rfd, NULL, NULL, NULL) < 0) {
timeout.tv_sec = 0;
timeout.tv_usec = SELECT_TIMEOUT;
if(select(MAX(xfd, cmdfd)+1, &rfd, NULL, NULL, &timeout) < 0) {
if(errno == EINTR)
continue;
die("select failed: %s\n", SERRNO);
}
if(FD_ISSET(cmdfd, &rfd)) {
ttyread();
stuff_to_print = 1;
}
if(stuff_to_print && last_draw_too_old()) {
stuff_to_print = 0;
draw();
}
while(XPending(xw.dpy)) {
XNextEvent(xw.dpy, &ev);
if(XFilterEvent(&ev, xw.win))