Construction of the <i>in silico</i> zebrafish.

<p>(A) A series of cross-sectional shapes is combined into a three-dimensional body model. The cross-section indicated in blue is shown in more detail in (B). (B) Generation of cross-section in the tail region: two “components”, body (green) and fin (blue), with different cross-sectional shapes are merged into a single cross-section (black). (C) Parameterisation (position, head orientation and body curvature) of the three-dimensional body model. The position of the tip of the snout is described by the coordinates <i>x</i>, <i>y</i>, <i>z</i>, and head orientation by the three Tait-Bryan angles <i>φ</i>_roll, <i>φ</i>_pitch, <i>φ</i>_yaw. Body deformation is parameterised by prescribing a curvature <i>κ</i> along the centreline (red) at a number of control points, indicated by the dots; the body surface is deformed along with the centreline, under the assumption that the transverse sections stay plane, and perpendicular to the centreline.