From 6370b79ebb4694e967b192a50cbb6811b26a351a Mon Sep 17 00:00:00 2001
From: paul <paul@plutz.net>
Date: Sun, 16 Apr 2017 22:54:19 +0000
Subject: [PATCH] jumping and better gravity handling

svn path=/trunk/; revision=11
---
 index.html | 80 ++++++++++++++++++++++++++----------------------------
 1 file changed, 39 insertions(+), 41 deletions(-)

diff --git a/index.html b/index.html
index ea0f3df..8f72f1e 100644
--- a/index.html
+++ b/index.html
@@ -11,7 +11,7 @@
       <tile position="3" elevation=".125"></tile>
       <tile position="4" blocking="yes"></tile>
     </tiles>
-    <img id="character" src="character.png" speed="2.75"/>
+    <img id="character" src="character.png" speed="4"/>
     <div id="map" columns="18" rows="36">
       5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
       5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
@@ -89,6 +89,7 @@
     </div>
   </canvas>
 </body><script>
+var gravity = 9.81, fps = 30;
 view = document.getElementById("view");
 canvas = document.getElementById("view").getContext("2d");
 
@@ -109,25 +110,25 @@ map = {
     this.sw = this.tw / 2;
     this.sh = this.th / 2;
 
+    this.gravity = gravity / fps / Math.sqrt(this.sw * this.sw + this.sh * this.sh) * this.sh;
+
     var prop, i;
 
     for (i in this.data) this.data[i] = this.data[i] * 1 || 0; // make numeric
 
     for (prop of document.querySelectorAll("tiles > tile")) {
       i = prop.getAttribute("position") * 1;
-      if (i) {
-        this.tileprops[i] = {
-          animated:  prop.getAttribute("animated")      || this.default_props.animated,
-          elevation: prop.getAttribute("elevation") * 1 || this.default_props.elevation,
-          blocking:  prop.getAttribute("blocking")      || this.default_props.blocking
-        }
+      if (i) this.tileprops[i] = {
+        animated:  prop.getAttribute("animated")      || this.default_props.animated,
+        elevation: prop.getAttribute("elevation") * 1 || this.default_props.elevation,
+        blocking:  prop.getAttribute("blocking")      || this.default_props.blocking
       }
     }
   },
 
   props_of: function(n) { return this.tileprops[this.data[n]] || this.default_props; },
 
-  tile_at: function(x, y) {
+  tile_at: function(x, y, z) {
     var my = (y / this.sh |0);
     var mx = (x / this.sw |0);
     
@@ -139,28 +140,29 @@ map = {
     }
     mx -= x / this.tw |0;
   
-    return this.cols * my + mx;
+    return this.cols * my + mx + (z |0) * this.rows * this.cols;
   },
 
   draw: function(){ // map.draw
     var py = player.n / this.cols % this.rows |0;
     var px = player.n % this.cols;
-    var x, y, z, n, tile;
+    var x, y, z, n, tile, props;
   
     for (y = 0; y < this.rows; ++y) {
       for (z = 0; z < this.data.length / (this.rows * this.cols); ++z)
       for (x = 0; x < this.cols; ++x) {
         n = x + y * map.cols + z * map.rows * map.cols;
+        props = this.props_of(n);
         tile = ( n == ptr ) ? 5 : this.data[n];
         canvas.globalAlpha = ( y > py &&
-                               (z > player.z || z == (player.z |0) && this.props_of(n).blocking) &&
+                               (z > player.z || z == (player.z |0) && props.blocking) &&
                                y < py + 6 &&
                                x > px - 2 &&
                                x < px + 2
                              ) ? .25 : 1;
   
         canvas.drawImage( this.tiles,
-                          this.tw * tile, 2 * this.th * ((frame / 16 |0) % 8),
+                          this.tw * tile, 2 * this.th * ((frame / 16 |0) % 8) * props.animated,
                           this.tw, 2 * this.th,
                           x * this.tw + y % 2 * this.sw - this.sw - this.offset_x,
                           y * this.sh - z * this.th - 3 * this.sh - this.offset_y,
@@ -181,13 +183,13 @@ player = {
     this.w = this.sprite.getAttribute("width")  * 1 || map.tw || 32;
     this.h = this.sprite.getAttribute("height") * 1 || map.sh * 6 || this.w * 1.5;
     this.o = this.sprite.getAttribute("offset") * 1 || map.sh || this.w / 4;
-    this.speed = this.sprite.getAttribute("speed") * 1|| this.w / 16;
-    this.n = map.tile_at(this.x, this.y) + this.z * map.rows * map.cols || 0;
+    this.ospeed = this.speed = this.sprite.getAttribute("speed") * 1|| this.w / 16;
+    this.n = map.tile_at(this.x, this.y, this.z);
     map.offset_x = this.x - view.clientWidth / 2 |0;
     map.offset_y = this.y - view.clientHeight / 2 |0;
   },
 
-  move: function(){
+  move: function(){ // player.move
     var dx = 0, dy = 0;
   
     switch(this.d){
@@ -209,41 +211,34 @@ player = {
       dy *= .625;
     }
   
-    var n = map.tile_at(this.x + dx, this.y + dy) + this.z * map.rows * map.cols;
+    var n = map.tile_at(this.x + dx, this.y + dy, this.z);
     if (!map.props_of(n).blocking &&
-        !map.props_of(n + map.rows * map.cols).blocking
-       ) { this.x += dx; this.y += dy; this.n = n; }
-    else if (!map.props_of(n + map.rows * map.cols).blocking &&
-             !map.props_of(n + 2 * map.rows * map.cols).blocking
-       ) { this.x += dx; this.y += dy; this.z += 1; this.n = n + map.rows * map.cols; }
+        !map.data[n + map.rows * map.cols]
+    ){ this.x += dx; this.y += dy; this.n = n;}
   
     this.frame += this.frame < 255 ? 1 : -127;
 
     map.offset_x = this.x - view.clientWidth / 2 |0;
     map.offset_y = this.y - view.clientHeight / 2 |0;
-  },
+  }, // end player.move
 
+  zspeed: 0,
   fall: function(){
-    if (!this.fallspeed) this.fallspeed = 0;
-    if (!this.falloff) this.falloff = 0;
+    var zbase = (this.n / (map.rows * map.cols) |0) + map.props_of(this.n).elevation;
 
-    if(this.falloff > 0 ||
-       !map.data[this.n] &&
-       !map.props_of(this.n - map.cols * map.rows).blocking
-      ) this.fallspeed += 1.81 * .03;
-    else this.fallspeed = 0;
+    this.z += this.zspeed -= map.gravity;
 
-    this.falloff -= this.fallspeed;
-    if (this.falloff < 0 &&
-        (map.data[this.n] ||
-         map.props_of(this.n - map.cols * map.rows).blocking)) {
-      this.fallspeed = this.falloff = 0;
-    } else if (this.falloff < 0) {
-      this.falloff += 1;
-      this.z -= 1;
+    if (this.z > zbase) {
+      this.speed = this.ospeed * 2;
+    } else if (!map.data[this.n] && !map.props_of(this.n - map.rows * map.cols).blocking) {
       this.n -= map.rows * map.cols;
+    } else {
+      this.speed = this.ospeed;
+      this.zspeed = 0;
+      this.z = zbase;
     }
-  },
+
+  }, // end player.fall
 
 
   draw: function(){ // player.draw
@@ -268,7 +263,7 @@ player = {
     canvas.drawImage( this.sprite, this.w * face, this.h * state,
                       this.w, this.h,
                       this.x - this.w / 2 - map.offset_x,
-                      this.y - (this.z |0) * map.th - this.h + this.o - map.offset_y - map.props_of(this.n).elevation * map.th - this.falloff * map.th,
+                      this.y - this.z * map.th - this.h + this.o - map.offset_y,
                       this.w, this.h );
    
   } // end player.draw
@@ -292,6 +287,9 @@ function get_input(){
     if ( player.frame > 11 ) player.frame = 0;
     player.move();
   }
+
+  // jump
+  if (keys[32] && player.zspeed == 0) {player.zspeed += .75; player.z +=.0001;}
 }
 
 function script(){
@@ -303,7 +301,7 @@ function script(){
     player.fall();
     map.draw();
     frame += frame < 255 ? 1 : -255;
-  }, 33)
+  }, 1000 / fps);
 
   window.addEventListener('keydown', function(x){ keys[x.keyCode] = true; }, false );
   window.addEventListener('keyup',   function(x){ keys[x.keyCode] = false;}, false );
@@ -312,7 +310,7 @@ function script(){
     px = view.width  * (e.clientX - view.offsetLeft) / view.clientWidth |0;
     py = view.height * (e.clientY - view.offsetTop) / view.clientHeight |0;
 
-    ptr = map.tile_at(px + map.offset_x, py + map.offset_y);
+    ptr = map.tile_at(px + map.offset_x, py + map.offset_y, 0);
   })
 }
 </script></html>
-- 
2.39.2