Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
--# Main
-- Terrain
function setup()
displayMode(FULLSCREEN)
forward, right, up = vec3(0,0,1), vec3(-1,0,0), vec3(0,1,0)
pos = vec3(0,100,0)
t = Terrain()
A = 0
end
function draw()
background(40, 40, 50)
perspective(45, WIDTH/HEIGHT, .1, 500000)
local m = matrix()
:rotate(RotationRate.z, forward.x,forward.y,forward.z)
:rotate(-RotationRate.x, right.x,right.y,right.z)
:rotate(-RotationRate.y, up.x,up.y,up.z)
forward, right, up = mult(m,forward),mult(m,right),mult(m,up)
local f = pos+forward
camera(pos.x,pos.y,pos.z,
f.x,f.y,f.z, up.x, up.y, up.z)
-- rotate(A,0,1,0)
translate(0,-5000,0)
rotate(-90,1,0,0)
t:draw(pos)
local v = 30000*DeltaTime
pos.x,pos.z = pos.x+forward.x*v,pos.z+forward.z*v
end
function mult(m, v) -- matrix multiplication
return vec3(
m[1]*v.x+m[2]*v.y+m[3]*v.z,
m[5]*v.x+m[6]*v.y+m[7]*v.z,
m[9]*v.x+m[10]*v.y+m[11]*v.z
)
end
function touched(touch)
if touch.state == MOVING then
A = A + touch.deltaX*.2
end
end
--# Terrain
Terrain = class()
function Terrain:init(x)
local d,s = 2000,20
self.d, self.s = d,s
self.m = mesh()
for y=-s,s do
for x=-s,s do
self.m:addRect(x*d,y*d,d,d)
end
end
self.m.texture = readImage("Cargo Bot:Crate Yellow 1")
self.m.shader = S
self.m:setColors(
color(65, 139, 41, 255))
end
function Terrain:draw(pos)
self.m.shader.light = vec3(math.cos(ElapsedTime),
math.sin(ElapsedTime),1):normalize()
pos =vec2(pos.x, pos.z)
local step = self.d*(self.s+.5)*2
local o = vec2(math.floor(pos.x/step+.5),
-math.floor(pos.y/step+.5))
-- drawing a 3x3 grid centered at camera position
for y=-1,1 do
for x=-1,1 do
pushMatrix()
local u,v = (o.x+x)*step,(o.y+y)*step
translate(u,v,0)
self.m.shader.offset = vec2(u,v)
self.m:draw()
popMatrix()
end
end
end
--# Perlin
Perlin = [[
//
// Description : Array and textureless GLSL 2D simplex noise function.
// Author : Ian McEwan, Ashima Arts.
// Maintainer : ijm
// Lastmod : 20110822 (ijm)
// License : Copyright (C) 2011 Ashima Arts. All rights reserved.
// Distributed under the MIT License. See LICENSE file.
// https://github.com/ashima/webgl-noise
//
vec3 mod289(vec3 x) {
return x - floor(x * (1.0 / 289.0)) * 289.0;
}
vec2 mod289(vec2 x) {
return x - floor(x * (1.0 / 289.0)) * 289.0;
}
vec3 permute(vec3 x) {
return mod289(((x*34.0)+1.0)*x);
}
float snoise(vec2 v)
{
const vec4 C = vec4(0.211324865405187, // (3.0-sqrt(3.0))/6.0
0.366025403784439, // 0.5*(sqrt(3.0)-1.0)
-0.577350269189626, // -1.0 + 2.0 * C.x
0.024390243902439); // 1.0 / 41.0
// First corner
vec2 i = floor(v + dot(v, C.yy) );
vec2 x0 = v - i + dot(i, C.xx);
// Other corners
vec2 i1;
//i1.x = step( x0.y, x0.x ); // x0.x > x0.y ? 1.0 : 0.0
//i1.y = 1.0 - i1.x;
i1 = (x0.x > x0.y) ? vec2(1.0, 0.0) : vec2(0.0, 1.0);
// x0 = x0 - 0.0 + 0.0 * C.xx ;
// x1 = x0 - i1 + 1.0 * C.xx ;
// x2 = x0 - 1.0 + 2.0 * C.xx ;
vec4 x12 = x0.xyxy + C.xxzz;
x12.xy -= i1;
// Permutations
i = mod289(i); // Avoid truncation effects in permutation
vec3 p = permute( permute( i.y + vec3(0.0, i1.y, 1.0 ))
+ i.x + vec3(0.0, i1.x, 1.0 ));
vec3 m = max(0.5 - vec3(dot(x0,x0), dot(x12.xy,x12.xy), dot(x12.zw,x12.zw)), 0.0);
m = m*m ;
m = m*m ;
// Gradients: 41 points uniformly over a line, mapped onto a diamond.
// The ring size 17*17 = 289 is close to a multiple of 41 (41*7 = 287)
vec3 x = 2.0 * fract(p * C.www) - 1.0;
vec3 h = abs(x) - 0.5;
vec3 ox = floor(x + 0.5);
vec3 a0 = x - ox;
// Normalise gradients implicitly by scaling m
// Approximation of: m *= inversesqrt( a0*a0 + h*h );
m *= 1.79284291400159 - 0.85373472095314 * ( a0*a0 + h*h );
// Compute final noise value at P
vec3 g;
g.x = a0.x * x0.x + h.x * x0.y;
g.yz = a0.yz * x12.xz + h.yz * x12.yw;
return 130.0 * dot(m, g);
}
]]
--# Shader
S = shader(Perlin .. [[
uniform mat4 modelViewProjection;
attribute vec4 position;
attribute vec4 color;
attribute vec2 texCoord;
uniform vec3 light;
uniform vec3 pos;
uniform vec2 offset;
varying lowp vec4 vColor;
varying highp vec2 vTexCoord;
varying lowp float vShade;
float h(vec2 p) {
p = p + offset;
return snoise(p*.001)*20. +
snoise((p-vec2(1.,1.))*.0001)*1000. +
snoise((p-vec2(1.,1.))*.00002)*5000.;
}
vec3 cnormal(vec2 p) {
float d = .01;
float h1 = h(p-vec2(d,0.)) - h(p+vec2(d,0.));
float h2 = h(p-vec2(0.,d)) - h(p+vec2(0.,d));
vec3 v = cross(vec3(d*2.,0.,h1),
vec3(0.,d*2.,h2));
return normalize(v);
}
void main() {
vColor = color;
vTexCoord = texCoord;
vec4 p = position;
p.z = p.z + h(p.xy);
if (light != vec3(0.,0.,0.)) {
lowp vec4 nor = vec4(cnormal(p.xy),0);
vShade = (dot(nor.xyz,light)+0.2)/1.2;
if (vShade >1.0) {vShade=1.0;}
if (vShade <0.2) {vShade=0.2;}
} else {
vShade = 1.;
}
gl_Position = modelViewProjection * p;
}
]], [[
uniform lowp sampler2D texture;
varying lowp vec4 vColor;
varying highp vec2 vTexCoord;
varying lowp float vShade;
void main() {
lowp vec4 res = texture2D(texture, vTexCoord);
lowp vec4 c = vColor;
c.rgb = c.rgb * vShade;
gl_FragColor = c;
}
]])
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.