+The core renders the board for the GUI and for graphical export plugins +(such as gerber, png, ps, etc.). In composite renders, when all layers +are combined to create a single image (e.g., GUI rendering, png export, +eps export), the order of layers matters: layers rendered later appear +being above layers rendered earlier. Furthermore some layers, like screen-only +marks, are not rendered in export targets. +
+With pcb-rnd versions newer than 2.3.1, rendering is controlled by the +render script which is stored in the config tree as appearance/render_script. +The render script is written in a Domain Specific Language designed +exclusively for this task so that it can be quick enough not to slow down +on-screen rendering. +
+The render script language consists of statements and comments. A comment +is anything from a hashmark (#) character to the end of the line. A statement +is a single line in one of two forms: +
+command [arg1 arg2 ... argN] +if cond1 [and cond2 ... and cond3] then command ++
+Commands can have zero or more arguments. Each argument is a single word. +Each 'if' applies only to one command, that is in the same line as +the 'if. Only the 'and' relation can be used between conditions of an 'if'. +All keywords are case sensitive. Below is the list of commands. +
+
| command | args | description + |
|---|---|---|
| stop | stop executing the script (render finished early; useful with 'if') + | |
| silk_tune_color | change the color of far_side silk layers to the configured "invisible" color (useful in screen rendering) + | |
| copper_order_UI | set up copper rendering order to match UI history: drw_copper will render current group on top, and then goes in order of how recently a group was selected + | |
| drw_copper | render copper layers in the selected order + | |
| drw_invis | render the invisible layer (if the GUI or export plugin accepts it; invisible layers include the far_side silk and doc layers) + | |
| drw_pstk | render padstacks (without holes) + | |
| drw_mask | render the mask layers + | |
| drw_layers | loc type | render all layer groups that match loc:type, in order they appear in the layer stackup. Loc is one of top, bottom, intern, global, this_side, far_side. + |
| drw_hole | render holes + | |
| drw_paste | render paste layers + | |
| drw_virtual | render virtual layers: auto generated assy and fab layers and cross-section + | |
| drw_ui_layers | render UI layers + | |
| drw_marks | render marks (subcircuit frames and IDs, terminal IDs, etc.) + | |
| drw_boundary_mech | render boundary and mech layers + |
+Conditions for an 'if' are: +
+
| condition | description + |
|---|---|
| GUI | true for on-screen (GUI) rendering, false for export + |
| check_planes |