//Copyright Chris Xiong 2018
//License: Expat (MIT)
var cvs,WGL,vpw,vph,hdiv;
var fsh=`
varying lowp vec4 vC;
void main(void)
{
gl_FragColor=vC;
}`;
var vsh=`
attribute vec3 vp;
attribute vec4 vc;
uniform mat4 mmodelview;
uniform mat4 mprojection;
varying lowp vec4 vC;
void main(void)
{
gl_Position=mprojection*mmodelview*vec4(vp,1.);
vC=vc;
}`;
var shp;
var vbufsize=4096;
var vbo,ibo;
var vb=new Float32Array(vbufsize*7);
var ib=new Uint16Array(vbufsize*6/4);
var Mprojection,Mmodelview;
var primc;
var kst=[];
var pos=[15,4,30];
var ofs=[0.9,3.5,20];
var mzw=50,mzh=35,ppx,ppy,ex,ey;
var maz=[];
var Sphere=function()
{
this.x=10-Math.random()*20;
this.y=10-Math.random()*20;
this.timer=0;this.r=0.2;
}
Sphere.prototype.update=function()
{
var d=Math.sqrt((this.x-pp.x)*(this.x-pp.x)+(this.y-pp.y)*(this.y-pp.y));
if(d<0.5&&this.timer===0)this.timer=1;
if(this.timer>0&&state===0)
{
++this.timer;health+=0.01;
this.r+=0.02;if(health>1)health=1;
}
if(this.timer>25)this.timer=-1;
}
Sphere.prototype.draw=function(x,y,a)
{
if(this.timer!==-1)pushSphere(x,y,0,this.r,[0,1,0,a*(0.6-this.timer*0.6/25)]);
}
function createShader(sh,t)
{
var shader=WGL.createShader(t);
WGL.shaderSource(shader,sh);
WGL.compileShader(shader);
if(!WGL.getShaderParameter(shader,WGL.COMPILE_STATUS))
{
alert("shader error..."+WGL.getShaderInfoLog(shader));
return null;
}
return shader;
}
function pushQuad(a)
{
if(primc>=vbufsize/4)batchGL();
for(var i=0;i<4;++i)
for(var j=0;j<7;++j)vb[primc*7*4+i*7+j]=a[i*7+j];
++primc;
}
function cube(x,y,z,l,r,g,b,a)
{
var L=x-l/2,R=x+l/2;
var B=y-l/2,T=y+l/2;
var N=z-l/2,F=z+l/2;
pushQuad([
L,B,N,r,g,b,a,
L,T,N,r,g,b,a,
R,T,N,r,g,b,a,
R,B,N,r,g,b,a
]);
pushQuad([
L,B,F,r,g,b,a,
L,T,F,r,g,b,a,
R,T,F,r,g,b,a,
R,B,F,r,g,b,a
]);
pushQuad([
L,B,N,r,g,b,a,
L,T,N,r,g,b,a,
L,T,F,r,g,b,a,
L,B,F,r,g,b,a
]);
pushQuad([
R,B,N,r,g,b,a,
R,T,N,r,g,b,a,
R,T,F,r,g,b,a,
R,B,F,r,g,b,a
]);
pushQuad([
L,B,N,r,g,b,a,
R,B,N,r,g,b,a,
R,B,F,r,g,b,a,
L,B,F,r,g,b,a
]);
pushQuad([
L,T,N,r,g,b,a,
R,T,N,r,g,b,a,
R,T,F,r,g,b,a,
L,T,F,r,g,b,a
]);
}
function pushSphere(x,y,z,r,col)
{
for(var i=0;i<12;++i)
for(var j=0;j<12;++j)
{
var r1=r*Math.sin(i*Math.PI/12);
var a=new v3d(x+r1*Math.cos(j*Math.PI/12*2),y+r1*Math.sin(j*Math.PI/12*2),z+r*Math.cos(i*Math.PI/12));
var b=new v3d(x+r1*Math.cos((j+1)*Math.PI/12*2),y+r1*Math.sin((j+1)*Math.PI/12*2),z+r*Math.cos(i*Math.PI/12));
r1=r*Math.sin((i+1)*Math.PI/12);
var c=new v3d(x+r1*Math.cos(j*Math.PI/12*2),y+r1*Math.sin(j*Math.PI/12*2),z+r*Math.cos((i+1)*Math.PI/12));
var d=new v3d(x+r1*Math.cos((j+1)*Math.PI/12*2),y+r1*Math.sin((j+1)*Math.PI/12*2),z+r*Math.cos((i+1)*Math.PI/12));
pushQuad([
a.x,a.y,a.z,col[0],col[1],col[2],col[3],
b.x,b.y,b.z,col[0],col[1],col[2],col[3],
d.x,d.y,d.z,col[0],col[1],col[2],col[3],
c.x,c.y,c.z,col[0],col[1],col[2],col[3]
]);
}
}
function randint(c)
{return Math.floor(Math.random()*c);}
function genmaze()
{
for(var i=0;i<mzw;++i)
{
maz[i]=[];
for(var j=0;j<mzh;++j)maz[i][j]=false;
}
var dx=[0,0,-1,1],
dy=[1,-1,0,0];
var lst=[];
var cx=randint(mzw),cy=randint(mzh);
lst.push({x:cx,y:cy,z:cx,w:cy});
while(lst.length)
{
var rm=lst.splice(randint(lst.length),1);
var x=rm[0].z,y=rm[0].w;
if(maz[x][y]==false)
{
maz[x][y]=maz[rm[0].x][rm[0].y]=true;
for(var i=0;i<4;++i)
{
cx=x+dx[i]*2;cy=y+dy[i]*2;
if(cx>=0&&cy>=0&&cx<mzw&&cy<mzh&&
maz[cx][cy]==false)
lst.push({x:x+dx[i],y:y+dy[i],z:cx,w:cy});
}
}
}
for(var i=0;i<mzh;++i)maz[0][i]=maz[mzw-1][i]=false;
for(var i=0;i<mzw;++i)maz[i][0]=maz[i][mzh-1]=false;
for(var i=0;i<mzh;++i){if(maz[1][i])lst.push({x:1,y:i});if(maz[mzw-2][i])lst.push({x:mzw-2,y:i});}
for(var i=0;i<mzw;++i){if(maz[i][1])lst.push({x:i,y:1});if(maz[i][mzh-2])lst.push({x:i,y:mzh-2});}
if(lst.length<2)return genmaze();
var rm=lst.splice(randint(lst.length),1);
ppx=rm[0].x,ppy=rm[0].y;
rm=lst.splice(randint(lst.length),1);
ex=rm[0].x,ey=rm[0].y;
}
function init()
{
cvs=document.getElementById("glCvs");
if(!window.devicePixelRatio)window.devicePixelRatio=1;
cvs.width=window.innerWidth;
cvs.height=window.innerHeight;
cvs.style.width=cvs.width+"px";
cvs.style.height=cvs.height+"px";
cvs.width=cvs.width*window.devicePixelRatio;
cvs.height=cvs.height*window.devicePixelRatio;
vpw=cvs.width;vph=cvs.height;
try
{WGL=cvs.getContext("webgl")||cvs.getContext("experimental-webgl");}
catch(e){WGL=null;}
if(!WGL){alert("WebGL is not supported by your browser...");return;}
WGL.clearColor(0.5,0.5,0.5,1.0);
WGL.clearDepth(1);
WGL.enable(WGL.DEPTH_TEST);
WGL.depthFunc(WGL.LESS);
WGL.enable(WGL.BLEND);
WGL.blendFunc(WGL.SRC_ALPHA,WGL.ONE_MINUS_SRC_ALPHA);
WGL.clear(WGL.COLOR_BUFFER_BIT|WGL.DEPTH_BUFFER_BIT);
WGL.viewport(0,0,cvs.width,cvs.height);
shp=WGL.createProgram();
var fshs=createShader(fsh,WGL.FRAGMENT_SHADER);
var vshs=createShader(vsh,WGL.VERTEX_SHADER);
WGL.attachShader(shp,vshs);WGL.attachShader(shp,fshs);
WGL.linkProgram(shp);
if(!WGL.getProgramParameter(shp,WGL.LINK_STATUS))
{
alert("shader link error...");
}
WGL.useProgram(shp);
vbo=WGL.createBuffer();
WGL.bindBuffer(WGL.ARRAY_BUFFER,vbo);
WGL.bufferData(WGL.ARRAY_BUFFER,vb,WGL.STATIC_DRAW);
var vpp=WGL.getAttribLocation(shp,"vp");
var vcp=WGL.getAttribLocation(shp,"vc");
WGL.enableVertexAttribArray(vpp);
WGL.enableVertexAttribArray(vcp);
WGL.bindBuffer(WGL.ARRAY_BUFFER,vbo);
WGL.vertexAttribPointer(vpp,3,WGL.FLOAT,false,7*4,0);
WGL.vertexAttribPointer(vcp,4,WGL.FLOAT,false,7*4,3*4);
for(var i=0,n=0,p=0;i<vbufsize/4;++i)
{
ib[p++]=n;ib[p++]=n+1;
ib[p++]=n+2;ib[p++]=n+2;
ib[p++]=n+3;ib[p++]=n;
n+=4;
}
ibo=WGL.createBuffer();
WGL.bindBuffer(WGL.ELEMENT_ARRAY_BUFFER,ibo);
WGL.bufferData(WGL.ELEMENT_ARRAY_BUFFER,ib,WGL.STATIC_DRAW);
document.addEventListener('keydown',function(e){kst[e.code]=1;});
document.addEventListener('keyup',function(e)
{
kst[e.code]=0;
if(e.code=='KeyD'){if(ppx+1<mzw&&maz[ppx+1][ppy])++ppx;}
if(e.code=='KeyA'){if(ppx-1>=0&&maz[ppx-1][ppy])--ppx;}
if(e.code=='KeyW'){if(ppy+1<mzh&&maz[ppx][ppy+1])++ppy;}
if(e.code=='KeyS'){if(ppy-1>=0&&maz[ppx][ppy-1])--ppy;}
});
genmaze();
requestAnimationFrame(mainloop);
}
function mainloop()
{
const ofx=-9,ofy=-11;
WGL.clearColor(0.5,0.5,0.5,1.0);
WGL.clearDepth(1);
WGL.clear(WGL.COLOR_BUFFER_BIT|WGL.DEPTH_BUFFER_BIT);
primc=0;
Mmodelview=buildIdentityMatrix();
Mmodelview=buildLookAtMatrix(pos,[15,10,0],[0,0,1]);
for(var i=0;i<mzw;++i)
for(var j=0;j<mzh;++j)
if(!maz[i][j])cube(i+ofx,j+ofy,0,1,0.1,0.1,0.1,1);
cube(ppx+ofx,ppy+ofy,0,0.6,0.1,0.8,0.1,1);
cube(ex+ofx,ey+ofy,0,0.8,0.4,0.9,0.9,1);
batchGL();
requestAnimationFrame(mainloop);
}
function batchGL()
{
Mprojection=buildProjectionMatrix3D(vpw,vph,60,0.1,100);
var mpp=WGL.getUniformLocation(shp,"mprojection");
WGL.uniformMatrix4fv(mpp,false,Mprojection);
var mvpp=WGL.getUniformLocation(shp,"mmodelview");
WGL.uniformMatrix4fv(mvpp,false,Mmodelview);
WGL.bindBuffer(WGL.ARRAY_BUFFER,vbo);
WGL.bufferData(WGL.ARRAY_BUFFER,vb,WGL.STATIC_DRAW);
WGL.drawElements(WGL.TRIANGLES,6*primc,WGL.UNSIGNED_SHORT,0);
primc=0;
}
