redraw optimization.

1 files changed, 24 insertions, 12 deletions

diff --git a/st.c b/st.c
index 0c6423a..4f17752 100644
--- a/st.c
+++ b/st.c
@@ -58,6 +58,7 @@ enum { GLYPH_SET=1, GLYPH_DIRTY=2 };
 enum { MODE_WRAP=1, MODE_INSERT=2, MODE_APPKEYPAD=4, MODE_ALTSCREEN=8 };
 enum { ESC_START=1, ESC_CSI=2, ESC_OSC=4, ESC_TITLE=8, ESC_ALTCHARSET=16 };
 enum { SCREEN_UPDATE, SCREEN_REDRAW };
+enum { WIN_VISIBLE=1, WIN_REDRAW=2, WIN_FOCUSED=4 };
 
 typedef struct {
         char c;     /* character code  */
@@ -117,8 +118,7 @@ typedef struct {
         int bufh; /* pixmap height */
         int ch; /* char height */
         int cw; /* char width  */
-        int focus;
-        int vis; /* is visible */
+        char state; /* focus, redraw, visible */
 } XWindow; 
 
 typedef struct {
@@ -1166,7 +1166,7 @@ tputc(char c) {
                         tnewline();
                         break;
                 case '\a':
-                        if(!xw.focus)
+                        if(!(xw.state & WIN_FOCUSED))
                                 xseturgency(1);
                         break;
                 case '\033':
@@ -1418,7 +1418,7 @@ xdrawcursor(void) {
                 xclear(oldx, oldy, oldx, oldy);
         
         /* draw the new one */
-        if(!(term.c.state & CURSOR_HIDE) && xw.focus) {
+        if(!(term.c.state & CURSOR_HIDE) && (xw.state & WIN_FOCUSED)) {
                 xdraws(&g.c, g, term.c.x, term.c.y, 1);
                 oldx = term.c.x, oldy = term.c.y;
         }
@@ -1458,7 +1458,7 @@ draw(int redraw_all) {
         Glyph base, new;
         char buf[DRAW_BUF_SIZ];
 
-        if(!xw.vis)
+        if(!(xw.state & WIN_VISIBLE))
                 return;
 
         xclear(0, 0, term.col-1, term.row-1);
@@ -1487,27 +1487,36 @@ draw(int redraw_all) {
         }
         xdrawcursor();
         XCopyArea(xw.dis, xw.buf, xw.win, dc.gc, 0, 0, xw.bufw, xw.bufh, BORDER, BORDER);
-        XFlush(xw.dis);
 }
 
 #endif
 
 void
 expose(XEvent *ev) {
-        draw(SCREEN_REDRAW);
+        XExposeEvent *e = &ev->xexpose;
+        if(xw.state & WIN_REDRAW) {
+                if(!e->count) {
+                        xw.state &= ~WIN_REDRAW;
+                        draw(SCREEN_REDRAW);
+                }
+        } else
+                XCopyArea(xw.dis, xw.buf, xw.win, dc.gc, e->x-BORDER, e->y-BORDER,
+                                e->width, e->height, e->x, e->y);
 }
 
 void
 visibility(XEvent *ev) {
         XVisibilityEvent *e = &ev->xvisibility;
-        /* XXX if this goes from 0 to 1, need a full redraw for next Expose,
-         * not just a buf copy */
-        xw.vis = e->state != VisibilityFullyObscured;
+        if(e->state == VisibilityFullyObscured)
+                xw.state &= ~WIN_VISIBLE;
+        else if(!(xw.state & WIN_VISIBLE))
+                /* need a full redraw for next Expose, not just a buf copy */
+                xw.state |= WIN_VISIBLE | WIN_REDRAW;
 }
 
 void
 unmap(XEvent *ev) {
-        xw.vis = 0;
+        xw.state &= ~WIN_VISIBLE;
 }
 
 void
@@ -1520,8 +1529,11 @@ xseturgency(int add) {
 
 void
 focus(XEvent *ev) {
-        if((xw.focus = ev->type == FocusIn))
+        if(ev->type == FocusIn) {
+                xw.state |= WIN_FOCUSED;
                 xseturgency(0);
+        } else
+                xw.state &= ~WIN_FOCUSED;
         draw(SCREEN_UPDATE);
 }