pulled out from my fork of upstream repo
This commit is contained in:
commit
f4605dbbd1
|
|
@ -0,0 +1,3 @@
|
|||
*.swp
|
||||
go.mod
|
||||
go.sum
|
||||
|
|
@ -0,0 +1,18 @@
|
|||
# go get -u github.com/faiface/pixel-examples
|
||||
# cd ~/go/src/github.com/faiface/pixel-examples/community/seascape-shader
|
||||
|
||||
all:
|
||||
GO111MODULE=off go build
|
||||
./seascape-shader
|
||||
|
||||
push:
|
||||
git pull
|
||||
git add --all
|
||||
-git commit -a -s
|
||||
git push
|
||||
|
||||
update:
|
||||
git pull
|
||||
|
||||
diff:
|
||||
git diff
|
||||
|
|
@ -0,0 +1,133 @@
|
|||
# Shadertoy to Pixel shader conversion
|
||||
|
||||
This will show you an example how you can take an example from [shadertoy.com](shadertoy.com) and use it with the Pixel Shader support.
|
||||
|
||||
["Seascape" by Alexander Alekseev aka TDM - 2014](https://www.shadertoy.com/view/Ms2SD1) is a nice one. It's very impressive and doesn't use textures so that simplifies things for us. Let's try that one.
|
||||
|
||||
Looking at the seascape.glsl example you can see **iResolution**, **iTime** and **iMouse** in there.
|
||||
|
||||
These are commonly needed to be exposed because these things are coming from outside and needs to be updated. Any other variable you need to have changed/updated from code can be exposed like those.
|
||||
|
||||
## Command line arguments
|
||||
|
||||
```
|
||||
./seascape-shader -h # will show you the command line options
|
||||
|
||||
./seascape-shader -filename ./shaders/seascape.glsl # Seascape
|
||||
./seascape-shader -filename ./shaders/planetfall.glsl # Planet Fall demo
|
||||
```
|
||||
|
||||
## Exposing variables
|
||||
|
||||
How to expose variables like this?
|
||||
|
||||
Well, first we need to figure out what type of variables they are. Looking at the shader, you can see **iResolution.x** in there. This tells you that it's not a simple type. In this case it's a **vec2***, a **Vector containing 2 values, x and y**. This makes sense since resolution is described by x and y. That is, width and height.
|
||||
|
||||
And thus, we create our variable in Go with like so:
|
||||
```
|
||||
uResolution := mgl32.Vec2{float32(win.Bounds().W()), float32(win.Bounds().H())}
|
||||
```
|
||||
That is, to be of the type **mgl32.Vec2**. Here we create it by taking the window's width and height.
|
||||
|
||||
**iTime** is just a float, and thus that is just created like so:
|
||||
```
|
||||
var uTime float32
|
||||
```
|
||||
|
||||
For the **iMouse**, it's a **mgl32.Vec4**, a **Vector containing 4 variables**. We only use x and y for the mouse position here though.
|
||||
```
|
||||
var uMouse mgl32.Vec4
|
||||
```
|
||||
|
||||
And finally, to make our variables available in the shader itself we use:
|
||||
```
|
||||
canvas.SetUniform(name string, value interface{})
|
||||
```
|
||||
|
||||
We create a handy function to do this:
|
||||
|
||||
``` go
|
||||
func EasyBindUniforms(c *pixelgl.Canvas, unifs ...interface{}) {
|
||||
if len(unifs)%2 != 0 {
|
||||
panic("needs to be divisable by 2")
|
||||
}
|
||||
for i := 0; i < len(unifs); i += 2 {
|
||||
|
||||
c.SetUniform(unifs[i+0].(string), unifs[i+1])
|
||||
}
|
||||
}
|
||||
```
|
||||
and we call that function like so:
|
||||
|
||||
``` go
|
||||
EasyBindUniforms(canvas,
|
||||
"uResolution", &uResolution,
|
||||
"uTime", &uTime,
|
||||
"uMouse", &uMouse,
|
||||
)
|
||||
```
|
||||
|
||||
## Updating shader source file
|
||||
|
||||
We also need to do some updates to the shader file itself to match these variables. First thing would be to add the variables we exposed in Go.
|
||||
|
||||
```
|
||||
uniform vec2 uResolution;
|
||||
uniform float uTime;
|
||||
uniform vec4 uMouse;
|
||||
```
|
||||
Then we just rename the variables to match.
|
||||
|
||||
We also need to rename the main function itself, as the one used here is specific for use with shadertoy. For our shader, the entrypoint is main(). So we rename:
|
||||
```
|
||||
void mainImage( out vec4 fragColor, in vec2 fragCoord )
|
||||
```
|
||||
to
|
||||
```
|
||||
void main() {
|
||||
```
|
||||
|
||||
|
||||
Also, rename:
|
||||
```
|
||||
fragCoord
|
||||
```
|
||||
to
|
||||
```
|
||||
gl_FragCoord
|
||||
```
|
||||
because this is available globaly in the OpenGL space for the shader.
|
||||
|
||||
We also need to add:
|
||||
```
|
||||
out vec4 fragColor;
|
||||
```
|
||||
|
||||
to expose that.
|
||||
|
||||
Lastly, we need to add:
|
||||
```
|
||||
#version 330 core
|
||||
```
|
||||
at the top to tell what version we require.
|
||||
|
||||
|
||||
## Using shader
|
||||
To use the shader in our canvas we do:
|
||||
```
|
||||
canvas.SetFragmentShader(fragSource string)
|
||||
```
|
||||
where fragSource is the fragment shader, not a path fo a file.
|
||||
|
||||
#
|
||||
|
||||
## Result converting shadertoy shader to use with Pixel
|
||||
|
||||
Here is a diff of the changes:
|
||||
|
||||
|
||||
|
||||
|
||||
And that is it. Running the program we should see this:
|
||||
|
||||
|
||||
|
|
@ -0,0 +1,79 @@
|
|||
package main
|
||||
|
||||
/*
|
||||
This simply parses the command line arguments using the default golang
|
||||
package called 'flag'. This can be used as a simple template to parse
|
||||
command line arguments in other programs.
|
||||
|
||||
It puts everything in the 'config' package which I think is a good
|
||||
wrapper around the 'flags' package and doesn't need a whole mess of
|
||||
global variables
|
||||
*/
|
||||
|
||||
import "log"
|
||||
import "os"
|
||||
import "flag"
|
||||
import "fmt"
|
||||
import "github.com/gookit/config"
|
||||
|
||||
var customUsage = func() {
|
||||
fmt.Fprintf(flag.CommandLine.Output(), "Usage of %s:\n", os.Args[0])
|
||||
flag.PrintDefaults()
|
||||
|
||||
fmt.Println("")
|
||||
fmt.Println("EXAMPLES:")
|
||||
fmt.Println("")
|
||||
fmt.Println(os.Args[0] + " --width 1024 --height 768 --drift .1 --filename shaders/seascape.glsl")
|
||||
fmt.Println(os.Args[0] + " --width 640 --height 480 --filename shaders/planetfall.glsl")
|
||||
fmt.Println("")
|
||||
}
|
||||
|
||||
func parseFlags() {
|
||||
var version string
|
||||
var race bool
|
||||
var filename string
|
||||
var width int
|
||||
var height int
|
||||
var glDrift float64
|
||||
|
||||
flag.StringVar (&version, "version", "v0.1", "Set compiled in version string")
|
||||
|
||||
flag.StringVar (&filename, "filename", "shaders/seascape.glsl", "path to GLSL file")
|
||||
flag.IntVar (&width, "width", 1024, "Width of the OpenGL Window")
|
||||
flag.IntVar (&height, "height", 768, "Height of the OpenGL Window")
|
||||
|
||||
flag.Float64Var (&glDrift, "drift", 0.01, "Speed of the gradual camera drift")
|
||||
flag.BoolVar (&race, "race", race, "Use race detector")
|
||||
|
||||
// Set the output if something fails to stdout rather than stderr
|
||||
flag.CommandLine.SetOutput(os.Stdout)
|
||||
|
||||
flag.Usage = customUsage
|
||||
flag.Parse()
|
||||
|
||||
if flag.Parsed() {
|
||||
log.Println("flag.Parse() worked")
|
||||
} else {
|
||||
log.Println("flag.Parse() failed")
|
||||
}
|
||||
|
||||
// keys := []string{"filename", "width", "height", "drift"}
|
||||
// keys := []string{"width", "height", "drift"}
|
||||
|
||||
// keys := []string{"height"}
|
||||
// config.LoadFlags(keys)
|
||||
|
||||
config.Set("width", width)
|
||||
config.Set("height", height)
|
||||
config.Set("glDrift", glDrift)
|
||||
config.Set("filename", filename)
|
||||
}
|
||||
|
||||
func parseConfig() {
|
||||
config.WithOptions(config.ParseEnv)
|
||||
parseFlags()
|
||||
|
||||
// config.LoadOSEnv([]string{"MAIL"})
|
||||
// config.LoadOSEnv([]string{"USER"})
|
||||
// config.LoadOSEnv([]string{"BUILDDEBUG"})
|
||||
}
|
||||
|
|
@ -0,0 +1,333 @@
|
|||
// Created by inigo quilez - iq/2018
|
||||
// License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
|
||||
|
||||
// Pretty much a modification to Klems' shader (https://www.shadertoy.com/view/XlcfRs)
|
||||
// Youtube version: https://www.youtube.com/watch?v=q1OBrqtl7Yo
|
||||
|
||||
#version 330 core
|
||||
|
||||
// Change AA to 1 if it renders too slow for you
|
||||
#define AA 1
|
||||
|
||||
uniform vec2 uResolution;
|
||||
uniform float uTime; // shader playback time (in seconds)
|
||||
uniform vec4 uMouse;
|
||||
|
||||
// there is tearing on my box. is this because this isn't working? -- jcarr
|
||||
uniform int iFrame; // shader playback frame
|
||||
|
||||
out vec4 fragColor;
|
||||
// in vec2 fragCoord;
|
||||
|
||||
mat3 makeBase( in vec3 w )
|
||||
{
|
||||
float k = inversesqrt(1.0-w.y*w.y);
|
||||
return mat3( vec3(-w.z,0.0,w.x)*k,
|
||||
vec3(-w.x*w.y,1.0-w.y*w.y,-w.y*w.z)*k,
|
||||
w);
|
||||
}
|
||||
|
||||
#define ZERO (min(iFrame,0))
|
||||
|
||||
// http://iquilezles.org/www/articles/intersectors/intersectors.htm
|
||||
vec2 sphIntersect( in vec3 ro, in vec3 rd, in float rad )
|
||||
{
|
||||
float b = dot( ro, rd );
|
||||
float c = dot( ro, ro ) - rad*rad;
|
||||
float h = b*b - c;
|
||||
if( h<0.0 ) return vec2(-1.0);
|
||||
h = sqrt(h);
|
||||
return vec2(-b-h,-b+h);
|
||||
}
|
||||
|
||||
// http://iquilezles.org/www/articles/distfunctions/distfunctions.htm
|
||||
float sdCapsule( in vec3 p, in float b, in float r )
|
||||
{
|
||||
float h = clamp( p.z/b, 0.0, 1.0 );
|
||||
return length( p - vec3(0.0,0.0,b)*h ) - r;//*(0.2+1.6*h);
|
||||
}
|
||||
|
||||
// modified Keinert et al's inverse Spherical Fibonacci Mapping
|
||||
vec4 inverseSF( in vec3 p, const in float n )
|
||||
{
|
||||
const float PI = 3.14159265359;
|
||||
const float PHI = 1.61803398875;
|
||||
|
||||
float phi = min(atan(p.y,p.x),PI);
|
||||
float k = max(floor(log(n*PI*sqrt(5.0)*(1.-p.z*p.z))/log(PHI+1.)),2.0);
|
||||
float Fk = pow(PHI,k)/sqrt(5.0);
|
||||
vec2 F = vec2(round(Fk),round(Fk*PHI));
|
||||
vec2 G = PI*(fract((F+1.0)*PHI)-(PHI-1.0));
|
||||
|
||||
mat2 iB = mat2(F.y,-F.x,G.y,-G.x)/(F.y*G.x-F.x*G.y);
|
||||
vec2 c = floor(iB*0.5*vec2(phi,n*p.z-n+1.0));
|
||||
|
||||
float ma = 0.0;
|
||||
vec4 res = vec4(0);
|
||||
for( int s=0; s<4; s++ )
|
||||
{
|
||||
vec2 uv = vec2(s&1,s>>1);
|
||||
float i = dot(F,uv+c);
|
||||
float phi = 2.0*PI*fract(i*PHI);
|
||||
float cT = 1.0 - (2.0*i+1.0)/n;
|
||||
float sT = sqrt(1.0-cT*cT);
|
||||
vec3 q = vec3(cos(phi)*sT, sin(phi)*sT,cT);
|
||||
float a = dot(p,q);
|
||||
if (a > ma)
|
||||
{
|
||||
ma = a;
|
||||
res.xyz = q;
|
||||
res.w = i;
|
||||
}
|
||||
}
|
||||
return res;
|
||||
}
|
||||
|
||||
float map( in vec3 p, out vec4 color, const in bool doColor )
|
||||
{
|
||||
float lp = length(p);
|
||||
float dmin = lp-1.0;
|
||||
{
|
||||
vec3 w = p/lp;
|
||||
vec4 fibo = inverseSF(w, 700.0);
|
||||
float hh = 1.0 - smoothstep(0.05,0.1,length(fibo.xyz-w));
|
||||
dmin -= 0.07*hh;
|
||||
color = vec4(0.05,0.1,0.1,1.0)*hh * (1.0+0.5*sin(fibo.w*111.1));
|
||||
}
|
||||
|
||||
|
||||
float s = 1.0;
|
||||
|
||||
for( int i=0; i<3; i++ )
|
||||
{
|
||||
float h = float(i)/float(3-1);
|
||||
|
||||
vec4 f = inverseSF(normalize(p), 65.0 + h*75.0);
|
||||
|
||||
// snap
|
||||
p -= f.xyz;
|
||||
|
||||
// orient to surface
|
||||
p = p*makeBase(f.xyz);
|
||||
|
||||
// scale
|
||||
float scale = 6.6 + 2.0*sin(111.0*f.w);
|
||||
p *= scale;
|
||||
p.xy *= 1.2;
|
||||
|
||||
//translate
|
||||
p.z -= 3.0 - length(p.xy)*0.6*sin(f.w*212.1);
|
||||
|
||||
// measure distance
|
||||
s *= scale;
|
||||
float d = sdCapsule( p, -6.0, 0.42 );
|
||||
d /= s;
|
||||
|
||||
if( d<dmin )
|
||||
{
|
||||
if( doColor )
|
||||
{
|
||||
color.w *= smoothstep(0.0, 5.0/s, dmin-d);
|
||||
|
||||
if( i==0 )
|
||||
{
|
||||
color.xyz = vec3(0.425,0.36,0.1)*1.1; // fall
|
||||
//color.xyz = vec3(0.4,0.8,0.1); // summer
|
||||
//color.xyz = vec3(0.4,0.4,0.8); // winter
|
||||
}
|
||||
|
||||
color.zyx += 0.3*(1.0-sqrt(h))*sin(f.w*1111.0+vec3(0.0,1.0,2.0));
|
||||
color.xyz = max(color.xyz,0.0);
|
||||
}
|
||||
dmin = d;
|
||||
}
|
||||
else
|
||||
{
|
||||
color.w *= 0.4*(0.1 + 0.9*smoothstep(0.0, 1.0/s, d-dmin));
|
||||
}
|
||||
}
|
||||
|
||||
return dmin;
|
||||
}
|
||||
|
||||
// http://iquilezles.org/www/articles/normalsSDF/normalsSDF.htm
|
||||
vec3 calcNormal( in vec3 pos, in float ep )
|
||||
{
|
||||
vec4 kk;
|
||||
#if 0
|
||||
vec2 e = vec2(1.0,-1.0)*0.5773;
|
||||
return normalize( e.xyy*map( pos + e.xyy*ep, kk, false ) +
|
||||
e.yyx*map( pos + e.yyx*ep, kk, false ) +
|
||||
e.yxy*map( pos + e.yxy*ep, kk, false ) +
|
||||
e.xxx*map( pos + e.xxx*ep, kk, false ) );
|
||||
#else
|
||||
// prevent the compiler from inlining map() 4 times
|
||||
vec3 n = vec3(0.0);
|
||||
for( int i=ZERO; i<4; i++ )
|
||||
{
|
||||
vec3 e = 0.5773*(2.0*vec3((((i+3)>>1)&1),((i>>1)&1),(i&1))-1.0);
|
||||
n += e*map(pos+e*ep, kk, false);
|
||||
}
|
||||
return normalize(n);
|
||||
#endif
|
||||
|
||||
}
|
||||
|
||||
// http://iquilezles.org/www/articles/rmshadows/rmshadows.htm
|
||||
float calcSoftshadow( in vec3 ro, in vec3 rd, float tmin, float tmax, const float k )
|
||||
{
|
||||
vec2 bound = sphIntersect( ro, rd, 2.1 );
|
||||
tmin = max(tmin,bound.x);
|
||||
tmax = min(tmax,bound.y);
|
||||
|
||||
float res = 1.0;
|
||||
float t = tmin;
|
||||
for( int i=0; i<50; i++ )
|
||||
{
|
||||
vec4 kk;
|
||||
float h = map( ro + rd*t, kk, false );
|
||||
res = min( res, k*h/t );
|
||||
t += clamp( h, 0.02, 0.20 );
|
||||
if( res<0.005 || t>tmax ) break;
|
||||
}
|
||||
return clamp( res, 0.0, 1.0 );
|
||||
}
|
||||
|
||||
float raycast(in vec3 ro, in vec3 rd, in float tmin, in float tmax )
|
||||
{
|
||||
vec4 kk;
|
||||
float t = tmin;
|
||||
for( int i=0; i<512; i++ )
|
||||
{
|
||||
vec3 p = ro + t*rd;
|
||||
float h = map(p,kk,false);
|
||||
if( abs(h)<(0.15*t/uResolution.x) ) break;
|
||||
t += h*0.5;
|
||||
if( t>tmax ) return -1.0;;
|
||||
}
|
||||
//if( t>tmax ) t=-1.0;
|
||||
|
||||
return t;
|
||||
}
|
||||
|
||||
// void mainImage( out vec4 fragColor, in vec2 fragCoord )
|
||||
// gl_FragCoord.xy
|
||||
void main()
|
||||
{
|
||||
float an = (uTime-10.0)*0.05;
|
||||
|
||||
// camera
|
||||
vec3 ro = vec3( 4.5*sin(an), 0.0, 4.5*cos(an) );
|
||||
vec3 ta = vec3( 0.0, 0.0, 0.0 );
|
||||
// camera-to-world rotation
|
||||
mat3 ca = makeBase( normalize(ta-ro) );
|
||||
|
||||
// render
|
||||
vec3 tot = vec3(0.0);
|
||||
|
||||
#if AA>1
|
||||
for( int m=ZERO; m<AA; m++ )
|
||||
for( int n=ZERO; n<AA; n++ )
|
||||
{
|
||||
// pixel coordinates
|
||||
vec2 o = vec2(float(m),float(n)) / float(AA) - 0.5;
|
||||
vec2 p = (-uResolution.xy + 2.0*(gl_FragCoord.xy+o))/uResolution.y;
|
||||
#else
|
||||
vec2 p = (-uResolution.xy + 2.0*gl_FragCoord.xy)/uResolution.y;
|
||||
#endif
|
||||
// ray direction
|
||||
vec3 rd = ca * normalize( vec3(p.xy,2.2) );
|
||||
|
||||
// background
|
||||
vec3 col = vec3(0.1,0.14,0.18) + 0.1*rd.y;
|
||||
|
||||
// bounding volume
|
||||
vec2 bound = sphIntersect( ro, rd, 2.1 );
|
||||
if( bound.x>0.0 )
|
||||
{
|
||||
// raycast
|
||||
float t = raycast(ro, rd, bound.x, bound.y );
|
||||
if( t>0.0 )
|
||||
{
|
||||
// local geometry
|
||||
vec3 pos = ro + t*rd;
|
||||
vec3 nor = calcNormal(pos, 0.01);
|
||||
vec3 upp = normalize(pos);
|
||||
|
||||
// color and occlusion
|
||||
vec4 mate; map(pos, mate, true);
|
||||
|
||||
// lighting
|
||||
col = vec3(0.0);
|
||||
|
||||
// key ligh
|
||||
{
|
||||
// dif
|
||||
vec3 lig = normalize(vec3(1.0,0.0,0.7));
|
||||
float dif = clamp(0.5+0.5*dot(nor,lig),0.0,1.0);
|
||||
float sha = calcSoftshadow( pos+0.0001*nor, lig, 0.0001, 2.0, 6.0 );
|
||||
col += mate.xyz*dif*vec3(1.8,0.6,0.5)*1.1*vec3(sha,sha*0.3+0.7*sha*sha,sha*sha);
|
||||
// spec
|
||||
vec3 hal = normalize(lig-rd);
|
||||
float spe = clamp( dot(nor,hal), 0.0, 1.0 );
|
||||
float fre = clamp( dot(-rd,lig), 0.0, 1.0 );
|
||||
fre = 0.2 + 0.8*pow(fre,5.0);
|
||||
spe *= spe;
|
||||
spe *= spe;
|
||||
spe *= spe;
|
||||
col += 1.0*(0.25+0.75*mate.x)*spe*dif*sha*fre;
|
||||
}
|
||||
|
||||
// back light
|
||||
{
|
||||
vec3 lig = normalize(vec3(-1.0,0.0,0.0));
|
||||
float dif = clamp(0.5+0.5*dot(nor,lig),0.0,1.0);
|
||||
col += mate.rgb*dif*vec3(1.2,0.9,0.6)*0.2*mate.w;
|
||||
}
|
||||
|
||||
// dome light
|
||||
{
|
||||
float dif = clamp(0.3+0.7*dot(nor,upp),0.0,1.0);
|
||||
#if 0
|
||||
dif *= 0.05 + 0.95*calcSoftshadow( pos+0.0001*nor, upp, 0.0001, 1.0, 1.0 );
|
||||
col += mate.xyz*dif*5.0*vec3(0.1,0.1,0.3)*mate.w;
|
||||
#else
|
||||
col += mate.xyz*dif*3.0*vec3(0.1,0.1,0.3)*mate.w*(0.2+0.8*mate.w);
|
||||
#endif
|
||||
}
|
||||
|
||||
// fake sss
|
||||
{
|
||||
float fre = clamp(1.0+dot(rd,nor),0.0,1.0);
|
||||
col += 0.3*vec3(1.0,0.3,0.2)*mate.xyz*mate.xyz*fre*fre*mate.w;
|
||||
}
|
||||
|
||||
// grade/sss
|
||||
{
|
||||
col = 2.0*pow( col, vec3(0.7,0.85,1.0) );
|
||||
}
|
||||
|
||||
// exposure control
|
||||
col *= 0.7 + 0.3*smoothstep(0.0,25.0,abs(uTime-31.0));
|
||||
|
||||
// display fake occlusion
|
||||
//col = mate.www;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
// gamma
|
||||
col = pow( col, vec3(0.4545) );
|
||||
|
||||
tot += col;
|
||||
#if AA>1
|
||||
}
|
||||
tot /= float(AA*AA);
|
||||
#endif
|
||||
|
||||
// vignetting
|
||||
vec2 q = gl_FragCoord.xy/uResolution.xy;
|
||||
tot *= pow( 16.0*q.x*q.y*(1.0-q.x)*(1.0-q.y), 0.2 );
|
||||
|
||||
fragColor = vec4( tot, 1.0 );
|
||||
}
|
||||
|
|
@ -0,0 +1,54 @@
|
|||
package main
|
||||
|
||||
import (
|
||||
"io/ioutil"
|
||||
|
||||
"github.com/faiface/pixel"
|
||||
"github.com/faiface/pixel/pixelgl"
|
||||
)
|
||||
|
||||
// Pixel Shader utility functions
|
||||
|
||||
// EasyBindUniforms does all the work for you, just pass in a
|
||||
// valid array adhering to format: String, Variable, ...
|
||||
//
|
||||
// example:
|
||||
//
|
||||
// var uTimeVar float32
|
||||
// var uMouseVar mgl32.Vec4
|
||||
//
|
||||
// EasyBindUniforms(win.GetCanvas(),
|
||||
// "u_time", &uTimeVar,
|
||||
// "u_mouse", &uMouseVar,
|
||||
// )
|
||||
//
|
||||
func EasyBindUniforms(c *pixelgl.Canvas, unifs ...interface{}) {
|
||||
if len(unifs)%2 != 0 {
|
||||
panic("needs to be divisable by 2")
|
||||
}
|
||||
for i := 0; i < len(unifs); i += 2 {
|
||||
|
||||
c.SetUniform(unifs[i+0].(string), unifs[i+1])
|
||||
}
|
||||
}
|
||||
|
||||
// CenterWindow will... center the window
|
||||
func CenterWindow(win *pixelgl.Window) {
|
||||
x, y := pixelgl.PrimaryMonitor().Size()
|
||||
width, height := win.Bounds().Size().XY()
|
||||
win.SetPos(
|
||||
pixel.V(
|
||||
x/2-width/2,
|
||||
y/2-height/2,
|
||||
),
|
||||
)
|
||||
}
|
||||
|
||||
// LoadFileToString loads the contents of a file into a string
|
||||
func LoadFileToString(filename string) (string, error) {
|
||||
b, err := ioutil.ReadFile(filename)
|
||||
if err != nil {
|
||||
return "", err
|
||||
}
|
||||
return string(b), nil
|
||||
}
|
||||
|
|
@ -0,0 +1,196 @@
|
|||
/*
|
||||
* "Seascape" by Alexander Alekseev aka TDM - 2014
|
||||
* License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
|
||||
* Contact: tdmaav@gmail.com
|
||||
*/
|
||||
|
||||
#version 330 core
|
||||
|
||||
uniform vec2 uResolution;
|
||||
uniform float uTime;
|
||||
uniform vec4 uMouse;
|
||||
|
||||
// This is how much you are drifting around. Zero means it only moves when the mouse moves
|
||||
uniform float uDrift;
|
||||
|
||||
out vec4 fragColor;
|
||||
|
||||
const int NUM_STEPS = 8;
|
||||
const float PI = 3.141592;
|
||||
const float EPSILON = 1e-3;
|
||||
#define EPSILON_NRM (0.1 / uResolution.x)
|
||||
|
||||
// sea
|
||||
const int ITER_GEOMETRY = 3;
|
||||
const int ITER_FRAGMENT = 5;
|
||||
const float SEA_HEIGHT = 0.6;
|
||||
const float SEA_CHOPPY = 4.0;
|
||||
const float SEA_SPEED = 0.8;
|
||||
const float SEA_FREQ = 0.16;
|
||||
const vec3 SEA_BASE = vec3(0.1,0.19,0.22);
|
||||
const vec3 SEA_WATER_COLOR = vec3(0.8,0.9,0.6);
|
||||
#define SEA_TIME (1.0 + uTime * SEA_SPEED)
|
||||
const mat2 octave_m = mat2(1.6,1.2,-1.2,1.6);
|
||||
|
||||
// math
|
||||
mat3 fromEuler(vec3 ang) {
|
||||
vec2 a1 = vec2(sin(ang.x),cos(ang.x));
|
||||
vec2 a2 = vec2(sin(ang.y),cos(ang.y));
|
||||
vec2 a3 = vec2(sin(ang.z),cos(ang.z));
|
||||
mat3 m;
|
||||
m[0] = vec3(a1.y*a3.y+a1.x*a2.x*a3.x,a1.y*a2.x*a3.x+a3.y*a1.x,-a2.y*a3.x);
|
||||
m[1] = vec3(-a2.y*a1.x,a1.y*a2.y,a2.x);
|
||||
m[2] = vec3(a3.y*a1.x*a2.x+a1.y*a3.x,a1.x*a3.x-a1.y*a3.y*a2.x,a2.y*a3.y);
|
||||
return m;
|
||||
}
|
||||
float hash( vec2 p ) {
|
||||
float h = dot(p,vec2(127.1,311.7));
|
||||
return fract(sin(h)*43758.5453123);
|
||||
}
|
||||
float noise( in vec2 p ) {
|
||||
vec2 i = floor( p );
|
||||
vec2 f = fract( p );
|
||||
vec2 u = f*f*(3.0-2.0*f);
|
||||
return -1.0+2.0*mix( mix( hash( i + vec2(0.0,0.0) ),
|
||||
hash( i + vec2(1.0,0.0) ), u.x),
|
||||
mix( hash( i + vec2(0.0,1.0) ),
|
||||
hash( i + vec2(1.0,1.0) ), u.x), u.y);
|
||||
}
|
||||
|
||||
// lighting
|
||||
float diffuse(vec3 n,vec3 l,float p) {
|
||||
return pow(dot(n,l) * 0.4 + 0.6,p);
|
||||
}
|
||||
float specular(vec3 n,vec3 l,vec3 e,float s) {
|
||||
float nrm = (s + 8.0) / (PI * 8.0);
|
||||
return pow(max(dot(reflect(e,n),l),0.0),s) * nrm;
|
||||
}
|
||||
|
||||
// sky
|
||||
vec3 getSkyColor(vec3 e) {
|
||||
e.y = max(e.y,0.0);
|
||||
return vec3(pow(1.0-e.y,2.0), 1.0-e.y, 0.6+(1.0-e.y)*0.4);
|
||||
}
|
||||
|
||||
// sea
|
||||
float sea_octave(vec2 uv, float choppy) {
|
||||
uv += noise(uv);
|
||||
vec2 wv = 1.0-abs(sin(uv));
|
||||
vec2 swv = abs(cos(uv));
|
||||
wv = mix(wv,swv,wv);
|
||||
return pow(1.0-pow(wv.x * wv.y,0.65),choppy);
|
||||
}
|
||||
|
||||
float map(vec3 p) {
|
||||
float freq = SEA_FREQ;
|
||||
float amp = SEA_HEIGHT;
|
||||
float choppy = SEA_CHOPPY;
|
||||
vec2 uv = p.xz; uv.x *= 0.75;
|
||||
|
||||
float d, h = 0.0;
|
||||
for(int i = 0; i < ITER_GEOMETRY; i++) {
|
||||
d = sea_octave((uv+SEA_TIME)*freq,choppy);
|
||||
d += sea_octave((uv-SEA_TIME)*freq,choppy);
|
||||
h += d * amp;
|
||||
uv *= octave_m; freq *= 1.9; amp *= 0.22;
|
||||
choppy = mix(choppy,1.0,0.2);
|
||||
}
|
||||
return p.y - h;
|
||||
}
|
||||
|
||||
float map_detailed(vec3 p) {
|
||||
float freq = SEA_FREQ;
|
||||
float amp = SEA_HEIGHT;
|
||||
float choppy = SEA_CHOPPY;
|
||||
vec2 uv = p.xz; uv.x *= 0.75;
|
||||
|
||||
float d, h = 0.0;
|
||||
for(int i = 0; i < ITER_FRAGMENT; i++) {
|
||||
d = sea_octave((uv+SEA_TIME)*freq,choppy);
|
||||
d += sea_octave((uv-SEA_TIME)*freq,choppy);
|
||||
h += d * amp;
|
||||
uv *= octave_m; freq *= 1.9; amp *= 0.22;
|
||||
choppy = mix(choppy,1.0,0.2);
|
||||
}
|
||||
return p.y - h;
|
||||
}
|
||||
|
||||
vec3 getSeaColor(vec3 p, vec3 n, vec3 l, vec3 eye, vec3 dist) {
|
||||
float fresnel = clamp(1.0 - dot(n,-eye), 0.0, 1.0);
|
||||
fresnel = pow(fresnel,3.0) * 0.65;
|
||||
|
||||
vec3 reflected = getSkyColor(reflect(eye,n));
|
||||
vec3 refracted = SEA_BASE + diffuse(n,l,80.0) * SEA_WATER_COLOR * 0.12;
|
||||
|
||||
vec3 color = mix(refracted,reflected,fresnel);
|
||||
|
||||
float atten = max(1.0 - dot(dist,dist) * 0.001, 0.0);
|
||||
color += SEA_WATER_COLOR * (p.y - SEA_HEIGHT) * 0.18 * atten;
|
||||
|
||||
color += vec3(specular(n,l,eye,60.0));
|
||||
|
||||
return color;
|
||||
}
|
||||
|
||||
// tracing
|
||||
vec3 getNormal(vec3 p, float eps) {
|
||||
vec3 n;
|
||||
n.y = map_detailed(p);
|
||||
n.x = map_detailed(vec3(p.x+eps,p.y,p.z)) - n.y;
|
||||
n.z = map_detailed(vec3(p.x,p.y,p.z+eps)) - n.y;
|
||||
n.y = eps;
|
||||
return normalize(n);
|
||||
}
|
||||
|
||||
float heightMapTracing(vec3 ori, vec3 dir, out vec3 p) {
|
||||
float tm = 0.0;
|
||||
float tx = 1000.0;
|
||||
float hx = map(ori + dir * tx);
|
||||
if(hx > 0.0) return tx;
|
||||
float hm = map(ori + dir * tm);
|
||||
float tmid = 0.0;
|
||||
for(int i = 0; i < NUM_STEPS; i++) {
|
||||
tmid = mix(tm,tx, hm/(hm-hx));
|
||||
p = ori + dir * tmid;
|
||||
float hmid = map(p);
|
||||
if(hmid < 0.0) {
|
||||
tx = tmid;
|
||||
hx = hmid;
|
||||
} else {
|
||||
tm = tmid;
|
||||
hm = hmid;
|
||||
}
|
||||
}
|
||||
return tmid;
|
||||
}
|
||||
|
||||
// main
|
||||
void main()
|
||||
{
|
||||
vec2 uv = gl_FragCoord.xy / uResolution.xy;
|
||||
uv = uv * 2.0 - 1.0;
|
||||
uv.x *= uResolution.x / uResolution.y;
|
||||
float time = uTime * uDrift * 5 + uMouse.x*0.01;
|
||||
|
||||
// ray
|
||||
vec3 ang = vec3(sin(time*3.0)*0.1,sin(time)*0.2+0.3,time);
|
||||
vec3 ori = vec3(0.0,3.5,time*5.0);
|
||||
vec3 dir = normalize(vec3(uv.xy,-2.0)); dir.z += length(uv) * 0.15;
|
||||
dir = normalize(dir) * fromEuler(ang);
|
||||
|
||||
// tracing
|
||||
vec3 p;
|
||||
heightMapTracing(ori,dir,p);
|
||||
vec3 dist = p - ori;
|
||||
vec3 n = getNormal(p, dot(dist,dist) * EPSILON_NRM);
|
||||
vec3 light = normalize(vec3(0.0,1.0,0.8));
|
||||
|
||||
// color
|
||||
vec3 color = mix(
|
||||
getSkyColor(dir),
|
||||
getSeaColor(p,n,light,dir,dist),
|
||||
pow(smoothstep(0.0,-0.05,dir.y),0.3));
|
||||
|
||||
// post
|
||||
fragColor = vec4(pow(color,vec3(0.75)), 1.0);
|
||||
}
|
||||
|
|
@ -0,0 +1,86 @@
|
|||
package main
|
||||
|
||||
import (
|
||||
"time"
|
||||
|
||||
"github.com/go-gl/mathgl/mgl32"
|
||||
|
||||
"github.com/faiface/pixel"
|
||||
"github.com/faiface/pixel/pixelgl"
|
||||
"golang.org/x/image/colornames"
|
||||
)
|
||||
|
||||
import "log"
|
||||
import "github.com/gookit/config"
|
||||
|
||||
func run() {
|
||||
// Set up window configs
|
||||
log.Println("width = ", config.Int("width"), "height = ", config.String("height"))
|
||||
cfg := pixelgl.WindowConfig{ // Default: 1024 x 768
|
||||
Title: "Golang GLSL",
|
||||
Bounds: pixel.R(0, 0, config.Float("width"), config.Float("height")),
|
||||
VSync: true,
|
||||
}
|
||||
|
||||
win, err := pixelgl.NewWindow(cfg)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
|
||||
camVector := win.Bounds().Center()
|
||||
|
||||
bounds := win.Bounds()
|
||||
bounds.Max = bounds.Max.ScaledXY(pixel.V(1.0, 1.0))
|
||||
|
||||
// I am putting all shader example initializing stuff here for
|
||||
// easier reference to those learning to use this functionality
|
||||
|
||||
log.Println("Load GSGL file = ", config.String("filename"))
|
||||
fragSource, err := LoadFileToString(config.String("filename"))
|
||||
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
|
||||
var uMouse mgl32.Vec4
|
||||
var uTime float32
|
||||
log.Println("glDrift = ", config.String("glDrift"))
|
||||
var glDrift float32 = float32(config.Float("glDrift"))
|
||||
|
||||
canvas := win.Canvas()
|
||||
uResolution := mgl32.Vec2{float32(win.Bounds().W()), float32(win.Bounds().H())}
|
||||
|
||||
EasyBindUniforms(canvas,
|
||||
"uResolution", &uResolution,
|
||||
"uTime", &uTime,
|
||||
"uMouse", &uMouse,
|
||||
"uDrift", &glDrift,
|
||||
)
|
||||
|
||||
canvas.SetFragmentShader(fragSource)
|
||||
|
||||
start := time.Now()
|
||||
|
||||
// Game Loop
|
||||
for !win.Closed() {
|
||||
uTime = float32(time.Since(start).Seconds())
|
||||
mpos := win.MousePosition()
|
||||
uMouse[0] = float32(mpos.X)
|
||||
uMouse[1] = float32(mpos.Y)
|
||||
|
||||
win.Clear(colornames.Black)
|
||||
|
||||
// Drawing to the screen
|
||||
canvas.Draw(win, pixel.IM.Moved(camVector))
|
||||
|
||||
win.Update()
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
func main() {
|
||||
// This parses the command line arguments
|
||||
parseConfig()
|
||||
|
||||
pixelgl.Run(run)
|
||||
}
|
||||
|
|
@ -0,0 +1,184 @@
|
|||
/*
|
||||
* "Seascape" by Alexander Alekseev aka TDM - 2014
|
||||
* License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
|
||||
* Contact: tdmaav@gmail.com
|
||||
*/
|
||||
|
||||
const int NUM_STEPS = 8;
|
||||
const float PI = 3.141592;
|
||||
const float EPSILON = 1e-3;
|
||||
#define EPSILON_NRM (0.1 / iResolution.x)
|
||||
|
||||
// sea
|
||||
const int ITER_GEOMETRY = 3;
|
||||
const int ITER_FRAGMENT = 5;
|
||||
const float SEA_HEIGHT = 0.6;
|
||||
const float SEA_CHOPPY = 4.0;
|
||||
const float SEA_SPEED = 0.8;
|
||||
const float SEA_FREQ = 0.16;
|
||||
const vec3 SEA_BASE = vec3(0.1,0.19,0.22);
|
||||
const vec3 SEA_WATER_COLOR = vec3(0.8,0.9,0.6);
|
||||
#define SEA_TIME (1.0 + iTime * SEA_SPEED)
|
||||
const mat2 octave_m = mat2(1.6,1.2,-1.2,1.6);
|
||||
|
||||
// math
|
||||
mat3 fromEuler(vec3 ang) {
|
||||
vec2 a1 = vec2(sin(ang.x),cos(ang.x));
|
||||
vec2 a2 = vec2(sin(ang.y),cos(ang.y));
|
||||
vec2 a3 = vec2(sin(ang.z),cos(ang.z));
|
||||
mat3 m;
|
||||
m[0] = vec3(a1.y*a3.y+a1.x*a2.x*a3.x,a1.y*a2.x*a3.x+a3.y*a1.x,-a2.y*a3.x);
|
||||
m[1] = vec3(-a2.y*a1.x,a1.y*a2.y,a2.x);
|
||||
m[2] = vec3(a3.y*a1.x*a2.x+a1.y*a3.x,a1.x*a3.x-a1.y*a3.y*a2.x,a2.y*a3.y);
|
||||
return m;
|
||||
}
|
||||
float hash( vec2 p ) {
|
||||
float h = dot(p,vec2(127.1,311.7));
|
||||
return fract(sin(h)*43758.5453123);
|
||||
}
|
||||
float noise( in vec2 p ) {
|
||||
vec2 i = floor( p );
|
||||
vec2 f = fract( p );
|
||||
vec2 u = f*f*(3.0-2.0*f);
|
||||
return -1.0+2.0*mix( mix( hash( i + vec2(0.0,0.0) ),
|
||||
hash( i + vec2(1.0,0.0) ), u.x),
|
||||
mix( hash( i + vec2(0.0,1.0) ),
|
||||
hash( i + vec2(1.0,1.0) ), u.x), u.y);
|
||||
}
|
||||
|
||||
// lighting
|
||||
float diffuse(vec3 n,vec3 l,float p) {
|
||||
return pow(dot(n,l) * 0.4 + 0.6,p);
|
||||
}
|
||||
float specular(vec3 n,vec3 l,vec3 e,float s) {
|
||||
float nrm = (s + 8.0) / (PI * 8.0);
|
||||
return pow(max(dot(reflect(e,n),l),0.0),s) * nrm;
|
||||
}
|
||||
|
||||
// sky
|
||||
vec3 getSkyColor(vec3 e) {
|
||||
e.y = max(e.y,0.0);
|
||||
return vec3(pow(1.0-e.y,2.0), 1.0-e.y, 0.6+(1.0-e.y)*0.4);
|
||||
}
|
||||
|
||||
// sea
|
||||
float sea_octave(vec2 uv, float choppy) {
|
||||
uv += noise(uv);
|
||||
vec2 wv = 1.0-abs(sin(uv));
|
||||
vec2 swv = abs(cos(uv));
|
||||
wv = mix(wv,swv,wv);
|
||||
return pow(1.0-pow(wv.x * wv.y,0.65),choppy);
|
||||
}
|
||||
|
||||
float map(vec3 p) {
|
||||
float freq = SEA_FREQ;
|
||||
float amp = SEA_HEIGHT;
|
||||
float choppy = SEA_CHOPPY;
|
||||
vec2 uv = p.xz; uv.x *= 0.75;
|
||||
|
||||
float d, h = 0.0;
|
||||
for(int i = 0; i < ITER_GEOMETRY; i++) {
|
||||
d = sea_octave((uv+SEA_TIME)*freq,choppy);
|
||||
d += sea_octave((uv-SEA_TIME)*freq,choppy);
|
||||
h += d * amp;
|
||||
uv *= octave_m; freq *= 1.9; amp *= 0.22;
|
||||
choppy = mix(choppy,1.0,0.2);
|
||||
}
|
||||
return p.y - h;
|
||||
}
|
||||
|
||||
float map_detailed(vec3 p) {
|
||||
float freq = SEA_FREQ;
|
||||
float amp = SEA_HEIGHT;
|
||||
float choppy = SEA_CHOPPY;
|
||||
vec2 uv = p.xz; uv.x *= 0.75;
|
||||
|
||||
float d, h = 0.0;
|
||||
for(int i = 0; i < ITER_FRAGMENT; i++) {
|
||||
d = sea_octave((uv+SEA_TIME)*freq,choppy);
|
||||
d += sea_octave((uv-SEA_TIME)*freq,choppy);
|
||||
h += d * amp;
|
||||
uv *= octave_m; freq *= 1.9; amp *= 0.22;
|
||||
choppy = mix(choppy,1.0,0.2);
|
||||
}
|
||||
return p.y - h;
|
||||
}
|
||||
|
||||
vec3 getSeaColor(vec3 p, vec3 n, vec3 l, vec3 eye, vec3 dist) {
|
||||
float fresnel = clamp(1.0 - dot(n,-eye), 0.0, 1.0);
|
||||
fresnel = pow(fresnel,3.0) * 0.65;
|
||||
|
||||
vec3 reflected = getSkyColor(reflect(eye,n));
|
||||
vec3 refracted = SEA_BASE + diffuse(n,l,80.0) * SEA_WATER_COLOR * 0.12;
|
||||
|
||||
vec3 color = mix(refracted,reflected,fresnel);
|
||||
|
||||
float atten = max(1.0 - dot(dist,dist) * 0.001, 0.0);
|
||||
color += SEA_WATER_COLOR * (p.y - SEA_HEIGHT) * 0.18 * atten;
|
||||
|
||||
color += vec3(specular(n,l,eye,60.0));
|
||||
|
||||
return color;
|
||||
}
|
||||
|
||||
// tracing
|
||||
vec3 getNormal(vec3 p, float eps) {
|
||||
vec3 n;
|
||||
n.y = map_detailed(p);
|
||||
n.x = map_detailed(vec3(p.x+eps,p.y,p.z)) - n.y;
|
||||
n.z = map_detailed(vec3(p.x,p.y,p.z+eps)) - n.y;
|
||||
n.y = eps;
|
||||
return normalize(n);
|
||||
}
|
||||
|
||||
float heightMapTracing(vec3 ori, vec3 dir, out vec3 p) {
|
||||
float tm = 0.0;
|
||||
float tx = 1000.0;
|
||||
float hx = map(ori + dir * tx);
|
||||
if(hx > 0.0) return tx;
|
||||
float hm = map(ori + dir * tm);
|
||||
float tmid = 0.0;
|
||||
for(int i = 0; i < NUM_STEPS; i++) {
|
||||
tmid = mix(tm,tx, hm/(hm-hx));
|
||||
p = ori + dir * tmid;
|
||||
float hmid = map(p);
|
||||
if(hmid < 0.0) {
|
||||
tx = tmid;
|
||||
hx = hmid;
|
||||
} else {
|
||||
tm = tmid;
|
||||
hm = hmid;
|
||||
}
|
||||
}
|
||||
return tmid;
|
||||
}
|
||||
|
||||
// main
|
||||
void mainImage( out vec4 fragColor, in vec2 fragCoord ) {
|
||||
vec2 uv = fragCoord.xy / iResolution.xy;
|
||||
uv = uv * 2.0 - 1.0;
|
||||
uv.x *= iResolution.x / iResolution.y;
|
||||
float time = iTime * 0.3 + iMouse.x*0.01;
|
||||
|
||||
// ray
|
||||
vec3 ang = vec3(sin(time*3.0)*0.1,sin(time)*0.2+0.3,time);
|
||||
vec3 ori = vec3(0.0,3.5,time*5.0);
|
||||
vec3 dir = normalize(vec3(uv.xy,-2.0)); dir.z += length(uv) * 0.15;
|
||||
dir = normalize(dir) * fromEuler(ang);
|
||||
|
||||
// tracing
|
||||
vec3 p;
|
||||
heightMapTracing(ori,dir,p);
|
||||
vec3 dist = p - ori;
|
||||
vec3 n = getNormal(p, dot(dist,dist) * EPSILON_NRM);
|
||||
vec3 light = normalize(vec3(0.0,1.0,0.8));
|
||||
|
||||
// color
|
||||
vec3 color = mix(
|
||||
getSkyColor(dir),
|
||||
getSeaColor(p,n,light,dir,dist),
|
||||
pow(smoothstep(0.0,-0.05,dir.y),0.3));
|
||||
|
||||
// post
|
||||
fragColor = vec4(pow(color,vec3(0.75)), 1.0);
|
||||
}
|
||||
Loading…
Reference in New Issue