User Tools
fdtd:geometry_modifiers
Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
|
fdtd:geometry_modifiers [2018/08/28 15:04] pklapetek |
fdtd:geometry_modifiers [2018/10/11 15:09] (current) pklapetek |
||
|---|---|---|---|
| Line 9: | Line 9: | ||
| ---- | ---- | ||
| // | // | ||
| - | {{ :samples:img_mod_roughen.png?100|}} | + | {{ :samples:img_mod_grow.png?100|}} |
| - | Sample parameter file: {{samples:mod_roughen.tar.gz|mod_roughen}}. | + | Sample parameter file: {{samples:mod_grow.tar.gz|mod_grow}}. |
| \\ | \\ | ||
| - | A 300x300x300 computational domain with a sphere modified by roughen. | + | A 200x200x200 computational domain with a sphere modified by growth. |
| // | // | ||
| ---- | ---- | ||
| - | The roughness can be also added by a simpler and faster procedure similar to addition of gaussian noise to an image (but done in 3D). Here, 3D gaussians are added to random places in the computational volume and using thresholding the new object surface is determined. | + | |
| + | Another possibility is to use vector displacement method, based on correlated noise | ||
| + | that is used to alter object boundaries. This is using a spectral synthesis approach | ||
| + | to create vector arrays of known variance and correlation length. | ||
| ---- | ---- | ||
| // | // | ||
| - | {{ :samples:img_mod_grow.png?100|}} | + | {{ :samples:spectral.png?100|}} |
| - | Sample parameter file: {{samples:mod_grow.tar.gz|mod_grow}}. | + | Sample parameter file: {{samples:mod_spectral.tar.gz|mod_spectral}}. |
| \\ | \\ | ||
| - | A 300x300x300 computational domain with a sphere modified by growth. | + | A 200x200x200 computational domain with a sphere modified by spectral synthesis based vector displacement. |
| // | // | ||
| ---- | ---- | ||
| + | The roughness can be also added by an alternative procedure similar to addition of correlated Gaussian noise to an image (but done in 3D). Here, the object position in the computational volume is represented by a probability of having the material on a certain place (1 means object, 0 no object at the beginning of calculation). 3D gaussians are added to random places in the computational volume and using thresholding the new object surface is determined. | ||
| + | |||
| + | ---- | ||
| + | // | ||
| + | {{ :samples:img_mod_roughen.png?100|}} | ||
| + | Sample parameter file: {{samples:mod_roughen.tar.gz|mod_roughen}}. | ||
| + | \\ | ||
| + | A 200x200x200 computational domain with a sphere modified by roughen. | ||
| + | // | ||
| + | ---- | ||
| + | Finally, we can use some function to modify the object shape. Again using an example from lower dimensions, | ||
| + | this is similar to adding e.g. small sine function signal to a 1D signal. Her, similarly to the MEDIUM_ROUGHEN directive, a probability map of finding material in a given voxel is created and then altered via an analytical expression given by user. | ||
| ---- | ---- | ||
| Line 34: | Line 49: | ||
| Sample parameter file: {{samples:mod_expression.tar.gz|mod_expression}}. | Sample parameter file: {{samples:mod_expression.tar.gz|mod_expression}}. | ||
| \\ | \\ | ||
| - | A 300x300x300 computational domain with a sphere modified by expression. | + | A 200x200x200 computational domain with a sphere modified by expression. |
| // | // | ||
| ---- | ---- | ||
fdtd/geometry_modifiers.1535461454.txt.gz · Last modified: 2018/08/28 15:04 by pklapetek
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial 4.0 International
