本教程详细讲解如何利用React-Three-Fiber实现动态图像效果,包括3D几何体构建、Canvas纹理映射、自定义着色器材质开发以及动画控制技术,最终打造出具有视觉冲击力的旋转图像塔效果。
使用React-Three-Fiber创建动态图像动画
视图与相机设置
通过低视场角(FOV=7)的透视相机模拟正交投影效果:
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<PerspectiveCamera
makeDefault
fov={7}
position={[0, 0, 70]}
near={0.01}
far={100000}
/>
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3D几何体构建
1. 广告牌组件(Billboard)
创建圆柱体作为图像展示载体:
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function Billboard({ radius = 5 }) {
return (
<mesh>
<cylinderGeometry args={[radius, radius, 2, 100, 1, true]} />
<meshBasicMaterial color="red" side={THREE.DoubleSide} />
</mesh>
);
}
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2. 横幅组件(Banner)
实现动态横幅效果:
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function Banner({ radius = 1.6 }) {
return (
<mesh>
<cylinderGeometry args={[radius, radius, radius*0.07, radius*80, 10, true]} />
<meshBasicMaterial color="blue" side={THREE.DoubleSide} />
</mesh>
);
}
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场景组装与布局
采用循环结构创建多层堆叠效果:
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const COUNT = 10;
const GAP = 3.2;
{Array.from({ length: COUNT }).map((_, index) => [
<Billboard
key={`billboard-${index}`}
position={[0, (index - (COUNT/2 - 1)) * GAP, 0]}
rotation={[0, index * Math.PI * 0.5, 0]}
/>,
<Banner
key={`banner-${index}`}
position={[0, (index - (COUNT/2 - 1)) * GAP - GAP*0.5, 0]}
rotation={[0, 0, 0.085]}
/>
])}
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Canvas纹理处理
图像预处理函数
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async function preloadImage(imageUrl, axis, canvasHeight, canvasWidth) {
const img = new Image();
await new Promise((resolve) => {
img.onload = resolve;
img.src = imageUrl;
});
const aspectRatio = img.naturalWidth / img.naturalHeight;
return {
img,
width: axis === 'x' ? canvasHeight * aspectRatio : canvasWidth,
height: axis === 'x' ? canvasHeight : canvasWidth / aspectRatio
};
}
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纹理映射技术
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function setupCylinderTextureMapping(texture, dimensions, radius) {
const circumference = 2 * Math.PI * radius;
const aspectRatio = circumference / 2;
if(dimensions.aspectRatio > aspectRatio) {
texture.repeat.x = aspectRatio / dimensions.aspectRatio;
texture.offset.x = (1 - texture.repeat.x)/2;
} else {
texture.repeat.y = dimensions.aspectRatio / aspectRatio;
}
texture.offset.y = (1 - texture.repeat.y)/2;
}
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动画实现
使用useFrame钩子实现纹理位移动画:
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useFrame((_, delta) => {
if(texture) texture.offset.x += delta * 0.001;
});
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高级材质开发
图像材质(背面变暗效果)
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if(!gl_FrontFacing) {
vec3 blackCol = vec3(0.0);
diffuseColor.rgb = mix(diffuseColor.rgb, blackCol, 0.7);
}
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横幅材质(渐变背景)
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vec3 pal(float t, vec3 a, vec3 b, vec3 c, vec3 d) {
return a + b*cos(6.28318*(c*t+d));
}
if(!gl_FrontFacing) {
diffuseColor.rgb = pal(vMapUv.x * repeatX, vec3(0.5), vec3(0.5), vec3(1.0), vec3(0.0,0.1,0.2));
}
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最终效果优化
- 整体倾斜角度调整:
rotation={[-0.15, 0, -0.2]}
- 纹理各向异性过滤:
map-anisotropy={16}
- 色调映射禁用:
toneMapped={false}
查看完整Demo | 获取源代码