一个Optical Stream 效果
使用cocos creator 3.10 版本
CCEffect %{
techniques:
-
passes:
-
vert: sprite-vs:vert
frag: sprite-fs:frag
depthStencilState:
depthTest: false
depthWrite: false
blendState:
targets:
-
blend: true
blendSrc: src_alpha
blendDst: one_minus_src_alpha
blendDstAlpha: one_minus_src_alpha
rasterizerState:
cullMode: none
properties:
iResolution:
value:
- 960
- 640
iMouse:
value:
- 0.5
- 0.5
- 0.5
- 0.5
alphaThreshold:
value: 0.5
}%
CCProgram sprite-vs %{
precision highp float;
#include <cc-global>
#if USE_LOCAL
#include <cc-local>
#endif
#if SAMPLE_FROM_RT
#include <common>
#endif
in vec3 a_position;
in vec2 a_texCoord;
in vec4 a_color;
out vec4 color;
out vec2 uv0;
vec4 vert () {
vec4 pos = vec4(a_position, 1);
#if USE_LOCAL
pos = cc_matWorld * pos;
#endif
#if USE_PIXEL_ALIGNMENT
pos = cc_matView * pos;
pos.xyz = floor(pos.xyz);
pos = cc_matProj * pos;
#else
pos = cc_matViewProj * pos;
#endif
uv0 = a_texCoord;
#if SAMPLE_FROM_RT
CC_HANDLE_RT_SAMPLE_FLIP(uv0);
#endif
color = a_color;
return pos;
}
}%
CCProgram sprite-fs %{
precision highp float;
#include <embedded-alpha>
#include <alpha-test>
#include <cc-global>
in vec4 color;
#if USE_TEXTURE
in vec2 uv0;
#pragma builtin(local)
layout(set = 2, binding = 10) uniform sampler2D cc_spriteTexture;
#endif
uniform Uniforms {
vec4 iMouse;
vec2 iResolution;
};
const float PI = 3.1415926;
vec3 rgb2hsv(vec3 hsv)
{
vec4 t = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
vec3 p = abs(fract(vec3(hsv.x) + t.xyz) * 6.0 - vec3(t.w));
return hsv.z * mix(vec3(t.x), clamp(p - vec3(t.x), 0.0, 1.0), hsv.y);
}
mat2 rotate(float a)
{
float s = sin(a);
float c = cos(a);
return mat2(
c, -s,
s, c
);
}
float rand(vec4 co)
{
return fract(sin(dot(co, vec4(12.9898, 78.233, 15.2358, 29.23851))) * 43758.5453);
}
float groundDist(vec3 pos)
{
pos.y += sin(pos.z * 0.2 + pos.x + cc_time[0] * 10.0) * 0.5;
pos.x = mod(pos.x, 4.0) - 2.0;
return length(pos.yx);
}
float particleDist(vec3 pos)
{
pos += cross(sin(pos * 0.05 + cc_time[0]), cos(pos * 0.05 + cc_time[0])) * 3.0;
pos.z += cc_time[0] * 200.0;
vec3 id = floor(pos / 16.0);
pos = mod(pos, 16.0) - 8.0;
pos += vec3(rand(vec4(id, 0.0)), rand(vec4(id, 1.0)), rand(vec4(id, 2.0))) * 10.0 - 5.0;
return max(length(pos.yx), abs(pos.z) - 2.0);
}
float skyDist(vec3 pos)
{
pos.z += cc_time[0] * 50.0;
vec3 id = floor(pos / 50.0);
vec3 t = cc_time[0] * vec3(0.0125, 0.25, 0.5);
vec3 a = vec3(rand(vec4(id, floor(t.x))), rand(vec4(id + 10.0, floor(t.y))), rand(vec4(id + 20.0, floor(t.z))));
vec3 b = vec3(rand(vec4(id, floor(t.x + 1.0))), rand(vec4(id + 10.0, floor(t.y + 1.0))), rand(vec4(id + 20.0, floor(t.z + 1.0))));
vec3 c = mix(a, b, pow(fract(t), vec3(1.0 / 4.0)));
float s = sign(mod(id.x + id.y + id.z + 0.5, 2.0) - 1.0);
vec3 u = cc_time[0] / 3.0 + vec3(1.0, 2.0, 3.0) / 3.0;
vec3 d = floor(u);
vec3 e = floor(u + 1.0);
vec3 f = mix(d, e, pow(fract(u), vec3(1.0 / 8.0)));
pos = mod(pos, 50.0) - 25.0;
for (int i = 0; i < 3; ++i)
{
pos.yz = rotate(f.x * PI / 2.0 * s) * pos.yz;
pos.xz = rotate(f.y * PI / 2.0 * s) * pos.xz;
pos.xy = rotate(f.z * PI / 2.0 * s) * pos.xy;
pos = abs(pos);
pos -= (c * 12.0);
pos *= 2.0;
if (pos.x > pos.z) pos.xz = pos.zx;
if (pos.y > pos.z) pos.yz = pos.zy;
if (pos.x < pos.y) pos.xy = pos.yx;
}
return length(pos.xz) / 8.0;
}
float dist(vec3 pos)
{
float d = 3.402823466E+38;
d = min(d, groundDist(pos));
d = min(d, skyDist(pos));
return d;
}
vec3 calcNormal(vec3 pos)
{
vec2 ep = vec2(0.001, 0.0);
return normalize(vec3(
dist(pos + ep.xyy) - dist(pos - ep.xyy),
dist(pos + ep.yxy) - dist(pos - ep.yxy),
dist(pos + ep.yyx) - dist(pos - ep.yyx)
));
}
vec3 calcColor(vec3 pos)
{
return rgb2hsv(vec3(pos.x * 0.04 + cc_time[0], 1, 1));
}
vec3 march(vec3 pos, vec3 dir)
{
vec3 color = vec3(0.0, 0.0, 0.0);
for (int i = 0; i < 32; ++i)
{
float d = dist(pos);
pos += dir * d * 0.9;
color += max(vec3(0.0), 0.02 / d * calcColor(pos));
}
return color;
}
vec3 marchParticle(vec3 pos, vec3 dir)
{
vec3 color = vec3(0.0, 0.0, 0.0);
for (int i = 0; i < 32; ++i)
{
float d = particleDist(pos);
pos += dir * d * 0.9;
color += max(vec3(0.0), 0.005 / d * vec3(1.0, 1.0, 1.0));
}
return color;
}
vec4 frag()
{
vec4 ssr_frag_out;
vec2 p = (gl_FragCoord.xy * 2.0 - iResolution.xy) / iResolution.y;
vec3 pos = vec3(0, 0.0, -10);
vec3 dir = normalize(vec3(p, 1.0));
dir.yz = rotate(-0.5) * dir.yz;
pos.yz = rotate(-0.5) * pos.yz;
dir.xz = rotate(sin(cc_time[0]) * 0.3) * dir.xz;
pos.xz = rotate(sin(cc_time[0]) * 0.3) * pos.xz;
dir.xy = rotate(0.1 + sin(cc_time[0] * 0.7) * 0.1) * dir.xy;
pos.xy = rotate(0.1 + sin(cc_time[0] * 0.7) * 0.1) * pos.xy;
vec3 color = vec3(0, 0, 0) * length(p.xy) * sin(cc_time[0] * 10.0);
color += march(pos, dir);
color += marchParticle(pos, dir);
ssr_frag_out = vec4(color, 1.0);
return ssr_frag_out;
}
}%