SceneKit中的iOS自定义几何体
我在尝试在iOS模拟器上运行带有纹理贴图的简单四边形时遇到困难。我已经阅读了关于这里的所有其他问题,这些问题涉及类似的事情,我被卡住了。输出如下所示: 纹理是这样的:SceneKit中的iOS自定义几何体,ios,objective-c,scenekit,Ios,Objective C,Scenekit,我在尝试在iOS模拟器上运行带有纹理贴图的简单四边形时遇到困难。我已经阅读了关于这里的所有其他问题,这些问题涉及类似的事情,我被卡住了。输出如下所示: 纹理是这样的: // v1 +----+ v0 // | | // v2 +----+ v3 SCNVector3 vertices[] = { SCNVector3Make( 5.0, 5.0, 0.0), SCNVector3Make( -5.0,
// v1 +----+ v0
// | |
// v2 +----+ v3
SCNVector3 vertices[] = { SCNVector3Make( 5.0, 5.0, 0.0),
SCNVector3Make( -5.0, 5.0, 0.0),
SCNVector3Make( -5.0, -5.0, 0.0),
SCNVector3Make( 5.0, -5.0, 0.0)
};
SCNVector3 normals[] = { SCNVector3Make( 0.0f, 0.0f, 1.0),
SCNVector3Make( 0.0f, 0.0f, 1.0),
SCNVector3Make( 0.0f, 0.0f, 1.0),
SCNVector3Make( 0.0f, 0.0f, 1.0)
};
CGPoint textureCoordinates[] = { CGPointMake( 1.0, 1.0),
CGPointMake( 0.0, 1.0),
CGPointMake( 0.0, 0.0),
CGPointMake( 1.0, 0.0)
};
NSUInteger vertexCount = 4;
NSMutableData *indicesData = [NSMutableData data];
UInt8 indices[] = { 0, 1, 2, 0, 2, 3};
[indicesData appendBytes:indices length:sizeof(UInt8)*6];
SCNGeometryElement *indicesElement = [SCNGeometryElement geometryElementWithData:indicesData
primitiveType:SCNGeometryPrimitiveTypeTriangles
primitiveCount:2
bytesPerIndex:sizeof(UInt8)];
NSMutableData *vertexData = [NSMutableData dataWithBytes:vertices length:vertexCount * sizeof(SCNVector3)];
SCNGeometrySource *verticesSource = [SCNGeometrySource geometrySourceWithData:vertexData
semantic:SCNGeometrySourceSemanticVertex
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:3
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(SCNVector3)];
NSMutableData *normalData = [NSMutableData dataWithBytes:normals length:vertexCount * sizeof(SCNVector3)];
SCNGeometrySource *normalsSource = [SCNGeometrySource geometrySourceWithData:normalData
semantic:SCNGeometrySourceSemanticNormal
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:3
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(SCNVector3)];
NSMutableData *textureData = [NSMutableData dataWithBytes:textureCoordinates length:vertexCount * sizeof(CGPoint)];
SCNGeometrySource *textureSource = [SCNGeometrySource geometrySourceWithData:textureData
semantic:SCNGeometrySourceSemanticTexcoord
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:2
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(CGPoint)];
SCNGeometry *geometry = [SCNGeometry geometryWithSources:@[verticesSource, normalsSource, textureSource]
elements:@[indicesElement]];
SCNMaterial *material = [SCNMaterial material];
//material.diffuse.contents = [UIColor redColor];
material.diffuse.contents = [UIImage imageNamed:@"diffuse.jpg"];
material.diffuse.wrapS = SCNWrapModeRepeat;
material.diffuse.wrapT = SCNWrapModeRepeat;
material.diffuse.contentsTransform = SCNMatrix4MakeScale( 1.0f, 1.0f, 1.0f);
material.doubleSided = YES;
material.normal.wrapS = SCNWrapModeRepeat;
material.normal.wrapT = SCNWrapModeRepeat;
// material.litPerPixel = YES;
geometry.materials = @[material];
我的代码是:
// v1 +----+ v0
// | |
// v2 +----+ v3
SCNVector3 vertices[] = { SCNVector3Make( 5.0, 5.0, 0.0),
SCNVector3Make( -5.0, 5.0, 0.0),
SCNVector3Make( -5.0, -5.0, 0.0),
SCNVector3Make( 5.0, -5.0, 0.0)
};
SCNVector3 normals[] = { SCNVector3Make( 0.0f, 0.0f, 1.0),
SCNVector3Make( 0.0f, 0.0f, 1.0),
SCNVector3Make( 0.0f, 0.0f, 1.0),
SCNVector3Make( 0.0f, 0.0f, 1.0)
};
CGPoint textureCoordinates[] = { CGPointMake( 1.0, 1.0),
CGPointMake( 0.0, 1.0),
CGPointMake( 0.0, 0.0),
CGPointMake( 1.0, 0.0)
};
NSUInteger vertexCount = 4;
NSMutableData *indicesData = [NSMutableData data];
UInt8 indices[] = { 0, 1, 2, 0, 2, 3};
[indicesData appendBytes:indices length:sizeof(UInt8)*6];
SCNGeometryElement *indicesElement = [SCNGeometryElement geometryElementWithData:indicesData
primitiveType:SCNGeometryPrimitiveTypeTriangles
primitiveCount:2
bytesPerIndex:sizeof(UInt8)];
NSMutableData *vertexData = [NSMutableData dataWithBytes:vertices length:vertexCount * sizeof(SCNVector3)];
SCNGeometrySource *verticesSource = [SCNGeometrySource geometrySourceWithData:vertexData
semantic:SCNGeometrySourceSemanticVertex
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:3
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(SCNVector3)];
NSMutableData *normalData = [NSMutableData dataWithBytes:normals length:vertexCount * sizeof(SCNVector3)];
SCNGeometrySource *normalsSource = [SCNGeometrySource geometrySourceWithData:normalData
semantic:SCNGeometrySourceSemanticNormal
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:3
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(SCNVector3)];
NSMutableData *textureData = [NSMutableData dataWithBytes:textureCoordinates length:vertexCount * sizeof(CGPoint)];
SCNGeometrySource *textureSource = [SCNGeometrySource geometrySourceWithData:textureData
semantic:SCNGeometrySourceSemanticTexcoord
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:2
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(CGPoint)];
SCNGeometry *geometry = [SCNGeometry geometryWithSources:@[verticesSource, normalsSource, textureSource]
elements:@[indicesElement]];
SCNMaterial *material = [SCNMaterial material];
//material.diffuse.contents = [UIColor redColor];
material.diffuse.contents = [UIImage imageNamed:@"diffuse.jpg"];
material.diffuse.wrapS = SCNWrapModeRepeat;
material.diffuse.wrapT = SCNWrapModeRepeat;
material.diffuse.contentsTransform = SCNMatrix4MakeScale( 1.0f, 1.0f, 1.0f);
material.doubleSided = YES;
material.normal.wrapS = SCNWrapModeRepeat;
material.normal.wrapT = SCNWrapModeRepeat;
// material.litPerPixel = YES;
geometry.materials = @[material];
[编辑]我用这段代码尝试了许多不同的方法,但似乎没有任何效果。我还没有在Objective-C中看到一个可以在iOS上运行的示例。对material.diffuse.wrapps的任何更改均无效
我以前在OpenGL中做过这样的事情,没有任何问题,但我已经盯着这段代码看了好几天,看不出我的错误。非常感谢您的帮助。@Paul Jan让我走上了正确的道路,这让我找到了以下答案: 将我的纹理坐标从CGPoint更改为float可以修复它
float textureCoordinates[] = { 1.0, 1.0,
0.0, 1.0,
0.0, 0.0,
1.0, 0.0
};
NSMutableData *textureData = [NSMutableData dataWithBytes:textureCoordinates length:vertexCount * sizeof(float) * 2];
SCNGeometrySource *textureSource = [SCNGeometrySource geometrySourceWithData:textureData
semantic:SCNGeometrySourceSemanticTexcoord
vectorCount:vertexCount
floatComponents:YES
componentsPerVector:2
bytesPerComponent:sizeof(float)
dataOffset:0
dataStride:sizeof(float) * 2];
结果:
在64位iOS上,CGFloat不是双精度的吗?您为textureSource的
byesPerComponent
指定sizeof(float)。很遗憾,没有区别,只是尝试了一下。谢谢您的快速回复。@Paul Jan请看下面我的答案,当我尝试您的建议时,我只在textureSource中更改了它,而没有在textureData中更改。再看一次,两个地方都变了,结果都成功了。如果你想把它写下来作为答案,我会接受,否则我会接受我自己的答案。这将给Paul Jan一个机会,让他先写下他的评论作为答案。请接受你自己的答案,你做了所有艰苦的工作,现在你的问答为知识的堆积如山增添了一笔:)