Note: this repo is not expected to be updated until at least summer 2014. There is also some new technology that I would like to use to make this project nicer and some parts of SceneKit that I have a much greater understanding of now that I would like to update.

DRMeshGeometry v0.3

DRMeshGeometryBuilder is a builder of static mesh geometry that makes it really easy to do 3D graphs in SceneKit.

The above geometry was generated with this code (available in the sampe project)

DRCartesianMeshGeometryBuilder *builder = [[DRCartesianMeshGeometryBuilder alloc] init];
builder.textureRepeatCounts = DRMeshCountMake(10, 10);
builder.xRange = DRMeshRangeMake(-20.0, 20.0);
builder.zRange = DRMeshRangeMake(-20.0, 20.0);

SCNGeometry *sine = [builder geometryWithCartesianFunction:^CGFloat(CGFloat x, CGFloat z) {
    return 2.0 * (sinf(.4*x) - cosf(.4*z));
}];

Once the geometry is generated it can be shaded using any light and material just like normal geometry in the scene.

Other coordinate systems

There is also similar builders to construct both cylindrical and spherical meshes, as seen below.

The following code generates the cylindrical mesh seen below

DRCylinderMeshGeometryBuilder *cylinderBuilder = [[DRCylinderMeshGeometryBuilder alloc] init];
cylinderBuilder.thetaRange = DRMeshRangeMake(0, 2.0*M_PI);
cylinderBuilder.yRange = DRMeshRangeMake(-10.0, 10.0);
cylinderBuilder.textureRepeatCounts = DRMeshCountMake(25, 4);

SCNGeometry *sine = [cylinderBuilder geometryWithCylinderFunction:^CGFloat(CGFloat theta, CGFloat y) {
    return 3.0*cosf(6.0*theta)+15.-0.5*y;
}];

In the same manner, this code generates the spherical mesh seen below

DRSphereMeshGeometryBuilder *sphereBuilder = [[DRSphereMeshGeometryBuilder alloc] init];
sphereBuilder.thetaRange = DRMeshRangeMake(0, M_PI);
sphereBuilder.psiRange   = DRMeshRangeMake(-M_PI_2, 1.25*M_PI);
sphereBuilder.textureRepeatCounts = DRMeshCountMake(6, 6);

SCNGeometry *sine = [sphereBuilder geometryWithSphereFunction:^CGFloat(CGFloat theta, CGFloat psi) {
    return -5.0*psi + 0.5*sinf(theta*30.0);
}];

Known limitations

• Currently only supports continous geometry.

If you need this or another addition or find a bug, please file an issue.

Future ideas

I’m also thinking of making the graph view into a component with properties for showing the axis and allowing the user to pan around.

New in v0.3

• Two finger trackpad gestures to pan, zoom and rotate.

New in v0.2

• Spherical and cylindrical mesh builders.