Configuration Options

DeepDrill is configured by specifying one or more profiles as command line parameters. Each profile contains a certain number of key-value pairs organized in sections. A typical profile looks like this:

[image]
width = 960
height = 540

[perturbation]
tolerance = 1e-6
rounds = 50

[approximation]
coefficients = 5

Each option is briefly explained below:

Key-value pairs

Section [location]

Key	Default value	Description
real	0.0	The real part of the image’s center coordiate.
imag	0.0	The imaginary part of the image’s center coordiate.
zoom	1.0	The magnification level of the image.
depth	1.0	The Maximum number of iterations.
escape	1e32	Once the iterated value gets bigger than this value, the corresponding coordinate is considered to be part of the Mandelbrot set.

Section [map]

Key	Default value	Description
width	1920	The horizontal resolution of the drill map. If this key is not specified, the width of the drill map is automatically chosen to match the image width.
height	1080	The vertical resolution of the drill map. If this key is not specified, the width of the drill map is automatically chosen to match the image height.

Section [mapfile]

| compress | yes | Indicates whether map files should be saved in compressed format.

Section [image]

Key	Default value	Description
width	1920	The horizontal resolution of the image in pixels.
height	1080	The vertical resolution of the image in pixels.

Section [video]

Key	Default value	Description
framerate	60	Frames per second of the computed video. By default, videos with 60 fps are computed to match the frame rate of standard TFTs.
keyframes	derived	Number of keyframes of the final video. If this key is not specified, DeepDrill derives the number from the zoom factor given in the location section.
startframe	0	Number of the keyframe where the video starts.
velocity	1.0	Zoom speed. The assigned value defines the time interval between two keyframes in seconds.
bitrate	8000	This value is passed directly to the FFmpeg backend. Higher values result in better image quality.

Section [palette]

Key	Default value	Description
image	-	Path to an image file storing the color palette. DeepDrill will derive the color palette from the uppermost horizontal line of the image.
bgcolor	black	Background color. This color is used for colorizing pixels belonging to the Mandelbrot set.
mode	smooth	Coloring mode. Options are classic and smooth.
scale	1.0	An optional scaling factor that can be used to stretch or shrink the color palette.
offset	-0.15	An optional offset that can be used to rotate the color palette.

Section [distance]

Key	Default value	Description
threshold	0.0	This value is used by the distance-estimation filter. A pixel is considered to be part of the Mandelbrot
set if its distance estimate is below the threshold value. Smaller numbers lead to more fine-grained images.

Section [texture]

Key	Default value	Description
image	-	Path to an overlay image. If an overlay image is specified, the derived color value will be mixed with the pixels from the overlay image.
opacity	0.5	The weight factor used to mix color pixels and overlay pixels.
scale	1.0	An optional scaling factor that can be used to stretch or shrink the overlay image.
offset	0.0	An optional offset that can be used to rotate the overlay image.

Section [lighting]

Key	Default value	Description
enable	no	Indicates whether the normal map should be utilized to create a spatial image.
alpha	45	The direction of the incoming light on the xy plane.
beta	45	The inclination of the light source.

Section [gpu]

Key	Default value	Description
colorizer	gradient.glsl	Path to a GLSL shader. The colorizer is the first of three GPU shaders. It utilzes the color palette to derive a RGB value for each pixel.
illuminator	lambert.glsl	Path to a GLSL shader. The illuminator is the second of three GPU shaders. It applies a lighting model to create a spatial images. This shader is skipped if lighting is disabled.
scaler	tricubic.glsl	Path to a GLSL shader. The scaler is the third of three GPU shaders. It scales the internal image down to the final image.

Section [perturbation]

Key	Default value	Description
enable	yes	Indicates if perturbation should be used to calculate the image. If set to false, DeepDrill falls back to the (very slow) standard algorithm.
tolerance	1e-6	This value is used by the perturbation algorithm. Please refer to the Theory section for details.
badpixels	0.001	Percentage of pixels that are allowed to be miscolored.
rounds	50	This value is used by the perturbation algorithm. Please refer to the Theory section for details.
color	black	Color used for colorizing glitch points.

Section [approximation]

Key	Default value	Description
enable	yes	Indicates if series approximation should be used to calculate the image. If set to false, the iteration always starts at 0. Please refer to the Theory section for details.
coefficients	5	This value is used by the series approximation algorithm. Please refer to the Theory section for details.
tolerance	1e-12	This value is used by the series approximation algorithm. Please refer to the Theory section for details.

Section [areachecking]

Key	Default value	Description
enable	yes	Specifies whether each pixel is to be tested for belonging to the main bulb or the cartioid. If the test is positive, the pixel is known to belong to the Mandelbrot set without further calculations.
color	black	Color used for colorizing pixels with a positive area check.

Section [attractorcheck]

Key	Default value	Description
enable	yes	Specifies whether attractor checking should be carried out. If the test is positive, the pixel is known to belong to the Mandelbrot set without further calculations.
tolerance	1e-34	Tolerance for considering two values as beeing equal.
color	black	Color used for colorizing pixels with a positive attractor check.

Section [periodcheck]

Key	Default value	Description
enable	yes	Specifies whether period checking should be carried out. If the test is positive, the pixel is known to belong to the Mandelbrot set without further calculations.
tolerance	1e-74	Tolerance for considering two values as beeing equal.
color	black	Color used for colorizing pixels with a positive period check.