Implement time-based lerp, footer animation

defs.jor

@@ -8,8 +8,9 @@ s" jorth.log" open const LOGFILE
 : 2dup over over ;
 : noop ;
 
+
 : defer word new-word docolon , ' noop , ' ret , ;
-: is ( cp -- ) word lookup drop cell + ! ;
+: redefine ( cp cpdeferred ) cell + ! ;
 
 : decompile
   word lookup if 1 begin ( cp i )

game.jor

@@ -1,6 +1,8 @@
 : blah
   ' seremit task-emit !
   ' log-emit task-echo ! ;
+blah
+' seremit task-emit !
 
 : start-repl activate blah
   s" .:: J O R T H ( jean forth) ::." type cr
@@ -51,6 +53,30 @@ defentity player
 100 player entity.x !
 100 player entity.y !
 
+( timer + lerping )
+: clamp0 ( range val -- i )
+  2dup  <= if drop else
+  dup 0 <= if drop drop 0 else
+	      swap drop then then ;
+: >ratio ( range value -- f )
+  over swap clamp0 >fix swap >fix fix/ ;
+: <ratio ( range ratio -- v )
+  swap >fix fix* <fix ;
+: >range ( start end -- start range ) over - ;
+: <range ( start range -- start end ) over + ;
+: lerpr ( start end ratio ) r> >range r< <ratio + ;
+: lerpn ( start1 end1 start2 end2 val )
+  r> >range r< rot - >ratio lerpr ;
+: lerp ( start end duration timer -- i )
+  @ ticks udelta ( start end duration delta )
+  >ratio lerpr ;
+
+: triggered ( duration timer -- b )
+  dup r> @ ticks udelta ( duration delta )
+  2dup <= if drop r< +! 1 else drop drop 0 then ;
+
+: now! ( timer -- ) ticks swap ! ;
+
 : tick-player
   0 ^LEFT key-down if 3 - W player entity.dir ! then
   ^RIGHT key-down if 3 + E player entity.dir ! then
@@ -59,6 +85,33 @@ defentity player
   ^DOWN key-down if 3 + S player entity.dir ! then
   player entity.y +! ;
 
+var MODE-TRAVEL
+var MODE-TEXT
+var split-timer
+
+: enter-mode-text
+  split-timer now!
+  MODE-TEXT @ ' tick redefine ;
+
+: mode-travel
+  tick-player
+  ^SPACE key-pressed if
+    enter-mode-text
+  then ;
+' mode-travel MODE-TRAVEL !
+
+: mode-text-hide
+  24 0 10 split-timer lerp dup split-screen
+  0 = if ' mode-travel ' tick redefine then ;
+
+: mode-text-show
+  0 24 10 split-timer lerp split-screen
+  ^SPACE key-pressed if
+    split-timer now!
+    ' mode-text-hide ' tick redefine
+  then ;
+' mode-text-show MODE-TEXT !
+
 : draw-player
   player entity.x @
   player entity.y @
@@ -75,5 +128,5 @@ defentity player
   600 600 2 draw-sprite
   draw-screen ;
 
-' tick-player is tick
+MODE-TRAVEL @ ' tick redefine
-' full-draw is draw
+' full-draw ' draw redefine

jorth.c

@@ -93,6 +93,23 @@ BINOP(f_or, u, ||)
 BINOP(f_bitand, u, &)
 BINOP(f_bitor, u, |)
 BINOP(f_bitxor, u, ^)
+BINOP(f_shr, u, >>)
+BINOP(f_shl, u, <<)
+
+void f_itofix() {
+  TOP().i = TOP().i << FIX_FRACTIONAL_BITS;
+}
+void f_fixtoi() {
+  TOP().i = TOP().i >> FIX_FRACTIONAL_BITS;
+}
+void f_fixmul() {
+  ST1().i = ((long)ST1().i * (long)TOP().i) / (1 << FIX_FRACTIONAL_BITS);
+  DROP(1);
+}
+void f_fixdiv() {
+  ST1().i = ((long)ST1().i * (1 << FIX_FRACTIONAL_BITS)) / TOP().i;
+  DROP(1);
+}
 
 void f_eq0() {
   TOP().i = (TOP().i == 0);
@@ -217,13 +234,13 @@ void f_word() {
   int key = ' ';
   int ibuf = 0;
 
-  while (key == ' ' || key == '\n' || key == '\r') {
+  while (key == ' ' || key == '\t' || key == '\n' || key == '\r') {
     f_key();
     key = TOP().i;
     DROP(1);
   }
 
-  while (key != ' ' && key != '\n' && key != '\r' && key != 0) {
+  while (key != ' ' && key != '\t' && key != '\n' && key != '\r' && key != 0) {
     buf[ibuf++] = key;
     f_key();
     key = TOP().i;
@@ -794,6 +811,12 @@ void f_init() {
   CDEF("&", f_bitand);
   CDEF("|", f_bitor);
   CDEF("^", f_bitxor);
+  CDEF("<<", f_shl);
+  CDEF(">>", f_shr);
+  CDEF(">fix", f_itofix);
+  CDEF("<fix", f_fixtoi);
+  CDEF("fix*", f_fixmul);
+  CDEF("fix/", f_fixdiv);
   CDEF("@", f_get);
   CDEF("!", f_set);
   CDEF("+!", f_addset);

jorth.h

@@ -3,6 +3,7 @@
 #define MEM_SIZE 16384
 #define STACK_SIZE 64
 #define RSTACK_SIZE 32
+#define FIX_FRACTIONAL_BITS 5
 
 void f_init();
 

testbed.c

@@ -175,7 +175,10 @@ void f_scroll() { // ( x y -- )
 void f_ticks() {
   PUSHU(timer_counter);
 }
-
+void f_splitscreen() {
+  setSplitScreen(399 - (TOP().i << 1));
+  DROP(1);
+}
 void game_f_init() {
   f_init();
   CDEF("seremit", f_seremit);
@@ -184,6 +187,7 @@ void game_f_init() {
   CDEF("draw-sprite", f_drawSprite);
   CDEF("scroll", f_scroll);
   CDEF("draw-screen", drawScreen);
+  CDEF("split-screen", f_splitscreen);
   CDEF("ticks", f_ticks);
 
   f_loadfile("game.jor");