这是一款基于HTML5的3D水波动画特效，它的效果非常逼真，水池中的石头在水中沉浮，泛起了一层层水波。同时我们可以拖拽鼠标从不同的视角来浏览水池，3D效果非常不错。另外，我们可以按“G”键来让水池中的石头上下浮动，按“L”键添加灯光效果，设计相当完美。同时说明一下，这款3D水波动画是基于WebGL渲染技术的，大家可以了解一下WebGL。
HTML代码
<img id="tiles" src="tiles.jpg"> <img id="xneg" src="xneg.jpg"> <img id="xpos" src="xpos.jpg"> <img id="ypos" src="ypos.jpg"> <img id="zneg" src="zneg.jpg"> <img id="zpos" src="zpos.jpg">
JavaScript代码
function Water() { var vertexShader = '\
varying vec2 coord;\
void main() {\
coord = gl_Vertex.xy * 0.5 + 0.5;\
gl_Position = vec4(gl_Vertex.xyz, 1.0);\
}\
'; this.plane = GL.Mesh.plane(); if (!GL.Texture.canUseFloatingPointTextures()) { throw new Error('This demo requires the OES_texture_float extension');
} var filter = GL.Texture.canUseFloatingPointLinearFiltering() ? gl.LINEAR : gl.NEAREST; this.textureA = new GL.Texture(256, 256, { type: gl.FLOAT, filter: filter }); this.textureB = new GL.Texture(256, 256, { type: gl.FLOAT, filter: filter }); this.dropShader = new GL.Shader(vertexShader, '\
const float PI = 3.141592653589793;\
uniform sampler2D texture;\
uniform vec2 center;\
uniform float radius;\
uniform float strength;\
varying vec2 coord;\
void main() {\
/* get vertex info */\
vec4 info = texture2D(texture, coord);\
\
/* add the drop to the height */\
float drop = max(0.0, 1.0 - length(center * 0.5 + 0.5 - coord) / radius);\
drop = 0.5 - cos(drop * PI) * 0.5;\
info.r += drop * strength;\
\
gl_FragColor = info;\
}\
'); this.updateShader = new GL.Shader(vertexShader, '\
uniform sampler2D texture;\
uniform vec2 delta;\
varying vec2 coord;\
void main() {\
/* get vertex info */\
vec4 info = texture2D(texture, coord);\
\
/* calculate average neighbor height */\
vec2 dx = vec2(delta.x, 0.0);\
vec2 dy = vec2(0.0, delta.y);\
float average = (\
texture2D(texture, coord - dx).r +\
texture2D(texture, coord - dy).r +\
texture2D(texture, coord + dx).r +\
texture2D(texture, coord + dy).r\
) * 0.25;\
\
/* change the velocity to move toward the average */\
info.g += (average - info.r) * 2.0;\
\
/* attenuate the velocity a little so waves do not last forever */\
info.g *= 0.995;\
\
/* move the vertex along the velocity */\
info.r += info.g;\
\
gl_FragColor = info;\
}\
'); this.normalShader = new GL.Shader(vertexShader, '\
uniform sampler2D texture;\
uniform vec2 delta;\
varying vec2 coord;\
void main() {\
/* get vertex info */\
vec4 info = texture2D(texture, coord);\
\
/* update the normal */\
vec3 dx = vec3(delta.x, texture2D(texture, vec2(coord.x + delta.x, coord.y)).r - info.r, 0.0);\
vec3 dy = vec3(0.0, texture2D(texture, vec2(coord.x, coord.y + delta.y)).r - info.r, delta.y);\
info.ba = normalize(cross(dy, dx)).xz;\
\
gl_FragColor = info;\
}\
'); this.sphereShader = new GL.Shader(vertexShader, '\
uniform sampler2D texture;\
uniform vec3 oldCenter;\
uniform vec3 newCenter;\
uniform float radius;\
varying vec2 coord;\
\
float volumeInSphere(vec3 center) {\
vec3 toCenter = vec3(coord.x * 2.0 - 1.0, 0.0, coord.y * 2.0 - 1.0) - center;\
float t = length(toCenter) / radius;\
float dy = exp(-pow(t * 1.5, 6.0));\
float ymin = min(0.0, center.y - dy);\
float ymax = min(max(0.0, center.y + dy), ymin + 2.0 * dy);\
return (ymax - ymin) * 0.1;\
}\
\
void main() {\
/* get vertex info */\
vec4 info = texture2D(texture, coord);\
\
/* add the old volume */\
info.r += volumeInSphere(oldCenter);\
\
/* subtract the new volume */\
info.r -= volumeInSphere(newCenter);\
\
gl_FragColor = info;\
}\
');
}
Water.prototype.addDrop = function(x, y, radius, strength) { var this_ = this; this.textureB.drawTo(function() {
this_.textureA.bind();
this_.dropShader.uniforms({
center: [x, y],
radius: radius,
strength: strength
}).draw(this_.plane);
}); this.textureB.swapWith(this.textureA);
};
Water.prototype.moveSphere = function(oldCenter, newCenter, radius) { var this_ = this; this.textureB.drawTo(function() {
this_.textureA.bind();
this_.sphereShader.uniforms({
oldCenter: oldCenter,
newCenter: newCenter,
radius: radius
}).draw(this_.plane);
}); this.textureB.swapWith(this.textureA);
};
Water.prototype.stepSimulation = function() { var this_ = this; this.textureB.drawTo(function() {
this_.textureA.bind();
this_.updateShader.uniforms({
delta: [1 / this_.textureA.width, 1 / this_.textureA.height]
}).draw(this_.plane);
}); this.textureB.swapWith(this.textureA);
};
Water.prototype.updateNormals = function() { var this_ = this; this.textureB.drawTo(function() {
this_.textureA.bind();
this_.normalShader.uniforms({
delta: [1 / this_.textureA.width, 1 / this_.textureA.height]
}).draw(this_.plane);
}); this.textureB.swapWith(this.textureA);
};本文链接：http://www.codeceo.com/article/html5-3d-wave-animation.html
本文作者：码农网 – 小峰