Package Jitter

jit.gl.lua

Script OpenGL and Jitter with Lua.

Description

jit.gl.lua provides and interface to both OpenGL and Jitter through the Lua scripting language. jit.gl.lua is similar to the js object for JavaScript.

Discussion

This object requires one argument: the name of a drawing context. A named drawing context is a named instance of a jit.window, jit.pwindow, or jit.matrix object that has an instance of the jit.gl.render object associated with it. Additionally it can reference the name of a jit.gl.node sub-context. This value may also be set via the OB3D drawto attribute. If no argument is present, the object is implicitly added to the first valid drawing context or sub-context found in the current patch or by searching up the patcher hierarchy.

Attributes

args[16 atoms]

any symbols or numbers can be entered that will be assigned to the Lua variable 'args'. args[1] is the first typed-in argument.

autowatch[int]

Enable autowatching of the loaded script file.

file[symbol]

The file to load.

gc[int]

Garbage collection flag.

inlets[int]

The number of inlets.

last_inlet[int]
read-only

With scripts with multiple inlets, this attribute tracks what inlet was last used by an incoming message, enabling scripts to generate different behavior depending on what inlet a message is sent to.

outlets[int]

The number of outlets.

path[symbol]
read-only

The path of the loaded script.

OB3D Attributes

anim[symbol]

The name of a jit.anim.node object that handles all spatial transforms for this instance (default = UID). The default value references an internal object, but can be overridden by setting to the name of an existing external jit.anim.node instance. This allows for more advanced control of the spatial transform.

anchor[3 floats]

The anchor position in local space (default = 0. 0. 0.). Allows for offsetting the local 3D origin around which transforms are applied.

animmode[symbol]

Determines which space the anim_move and anim_turn messages will affect the position and orientation of this object (default = parent).
local = Rotate relative to local axis
parent = Rotate relative to parent axis
world = Rotate relative to world axis

antialias[int]

Antialiasing flag (default = 0) On some hardware, the blend_enable attribute must also be enabled for antialiasing to work.

automatic[int]

Automatic rendering flag (default = 1) When the flag is set, rendering occurs when the associated jit.gl.render object receives a bang message

auto_material[int]

Automatic material attributes flag (default = 1) When the flag is set, and lighting is enabled for the object, the diffuse and ambient material components for the object will be set to the object's color, and the specular and emissive lighting components are disabled.

aux_color[4 floats]

The auxiliary color in the form red green blue alpha (default = 0. 0. 0. 0.) The list elements should be in the range 0.-1.

axes[int]

x/y/z axis rendering off/on (default = 0)

blend[symbol]

The named blending mode. The possible values are:
add = blend_mode 1 1
multiply = blend_mode 2 1
screen = blend_mode 4 1
exclusion = blend_mode 4 5
colorblend = blend_mode 3 4
alphablend = blend_mode 6 7
coloradd = blend_mode 3 1
alphaadd = blend_mode 6 1

blend_enable[int]

Blending flag (default = 0) When the flag is set, blending is enabled for all rendered objects.

blend_mode[2 ints]

The source and destination planes associated with the blend mode (default = 6 7) Blend modes are specified in the form src_blend_mode dst_blend_mode. The supported modes are:
0 = zero
1 = one
2 = destination color
3 = source color
4 = one minus destination color
5 = one minus source color
6 = source alpha
7 = one minus source alpha
8 = destination alpha
9 = one minus destination alpha
10 = source alpha saturate

capture[symbol]

The name of a texture to be rendered to - e.g. jit.gl.nurbs @capture mytex will capture to jit.gl.texture @name mytex .

cull_face[int]

Face culling mode (default = 0 (no culling))
0 = no culling
1 = cull back faces
2 = cull front faces

depth_clear[int]

Depth buffer clear flag (default = 0) When the flag is set, the depth buffer is cleared before rendering the object.

depth_enable[int]

Depth buffering flag (default = 1) When the flag is set, depth buffering is enabled.

depth_write[int]

Depth write flag (default = 1). When the flag is set, writing to the depth buffer is enabled. This will have no effect if depth_enable is turned off.

drawto[symbol]

The named drawing context in which to draw (default = none) A named drawing context is a named instance of a jit.window, jit.pwindow, or jit.matrix object that has an instance of the jit.gl.render object associated with it.

enable[int]

Enable flag (default = 1) When the flag is set, drawing is enabled.

filterclass[symbol]

The name of this object's pick filter class (default = default). This controls the visibility of objects to the jit.gl.handle and jit.gl.picker objects. In order to select this object, the filterclass value must be in the picking object's filters list.

fog_params[7 floats]

The fog parameters in the form red green blue alpha density start end (default = 0. 0. 0. 0. 0. 0. 0.) The list's color elements should be in the range 0.-1.

fog[float]

The amount of fog effect (default = 0.)

layer[int]

Object layer number (default = 0) When in automatic mode, the layer number determines the rendering order (low to high). Objects in the same layer have no guarantee which will be rendered first.

lighting_enable[int]

Lighting enabled flag (default = 0) When the flag is set, lighting is calculated.

line_width[float]

The drawing line width (default = 1.)

mat_ambient[4 floats]

The ambient light material property in the form red green blue alpha (default = 0. 0. 0. 0.) The list elements should be in the range 0.-1.

mat_diffuse[4 floats]

The diffuse light material property in the form red green blue alpha (default = 0. 0. 0. 0.) The list elements should be in the range 0.-1.

mat_emission[4 floats]

The material emission property in the form red green blue alpha (default = 0. 0. 0. 0.) The list elements should be in the range 0.-1.

mat_specular[4 floats]

The specular light material property in the form red green blue alpha (default = 0. 0. 0. 0.) The list elements should be in the range 0.-1.

matfile[symbol]

The Jitter material file to apply (.jitmtl)

matrixoutput[int]

Matrix output mode (default = 0)
0 = issue render commands
1 = output geometry matrices
2 = output geometry matrices with local transform applied

name[symbol]

The instance name (default = UID)

point_mode[symbol]

Point drawing mode to use when points drawing primitive (poly_mode 2) is enabled (default = circle). Possible values:

'square' ( Draw point as square )
'circle' ( Draw point as circle )
'square_depth' ( Draw point as square with depth scaling )
'circle_depth' ( Draw point as circle with depth scaling )
'user_shader' ( Allow writing to gl_PointSize in custom vertex shader )

point_size[float]

The draw point size (default = 1.)

poly_mode[2 ints]

Polygon rendering modes (default 0 0) Rendering modes are expressed in the form frontface backface. Supported rendering modes are:
0 = render as filled polygons
1 = render as lines
2 = render as points

position[3 floats]

The 3D origin in the form x y z (default = 0. 0. 0.)

quat[4 floats]

The current rotation as a quaternion(default = 0. 0. 0. 1.). A quaternion is a mathematical construct that is a four dimensional vector, and can be visualized as a rotation around an arbitrary axis. Quaternions are a useful representation of an orientation in 3D space.

rotate[4 floats]

The angle of rotation and the xyz vector about which the rotation is performed in the form rotation-angle x y z (default = 0. 0. 0. 1.)

rotatexyz[3 floats]

Sets the current rotation to the concatenation of rotations about the positive x, y, and z axes, also known as Euler angles (default = 0. 0. 0.). The default order is yzx and can be changed with the jit.gl.render rotate_order attribute. Angles are expressed in degrees.

scale[3 floats]

The 3D scaling factor in the form x y z (default = 1. 1. 1.)

shadow_caster[int]

Shadow caster flag (default = 0) When the flag is set, object will cast shadows.

shininess[float]

The material shininess value (default = 16.0) The value should be a float in the range 0.-255.

smooth_shading[int]

Smooth shading flag (default = 0) When the flag is set, smooth shading is used when rendering.

tex_map[int]

Mode for automatic generation of texture coordinate controls (default = 0)
0 = no coordinates are generated.
1 = OpenGL's texture generation is used with mode GL_OBJECT_LINEAR. This applies the texture in a fixed orientation relative to the object.
2 = OpenGL's texture generation is used with mode GL_SPHERE_MAP. This can be used to create a reflection effect.
3 = OpenGL's texture generation is used with mode GL_EYE_LINEAR. This applies the texture in a fixed orientation relative to OpenGL's eye coordinates.
Modes 1 and 3 are affected by the value of the tex_plane_s and tex_plane_t attributes listed below.

tex_plane_s[4 floats]

The texture generation coefficients a b c d that apply to tex_map modes 1 and 3. (default = 1. 0. 0. 0.)
The four coefficients define a plane used to generate the s texture coordinate, which corresponds to the x axis of the texture image. If the tex_map mode is 1, s = ax + by + cz + dw, where x, y, z, and w are the homogeneous coordinates of the vertex.

tex_plane_t[4 floats]

The texture generation coefficients a b c d, which apply to tex_map modes 1 and 3. (default = 0. 1. 0. 0)
The four coefficients define a plane which is used to generate the t texture coordinate, which corresponds to the y axis of the texture image.

shader[symbol]

The name of the shader to be applied (default = none)

texture[8 symbols]

The name of the texture to be applied (default = none). If multiple textures are specified, uses multi-texturing.

transform_reset[int]

Modelview and projection transform reset flag (default = 0) When the flag is set, the modelview and projection transforms are set to the identity transform before rendering the object. This is useful for sprite or billboard overlays, or automatic scaling to window size. The transform_reset flag modes are:
0 = do nothing (default)
1 = proportional orthographic glOrtho(-aspect, aspect, -1.0, 1.0, near_clip, far_clip);
2 = orthographic normalized glOrtho(-1.0, 1.0, -1.0, 1.0, near_clip, far_clip);
3 = proportional perspective with near clip = 0.001 gluPerspective(lens_angle, aspect, 0.001/*near_clip*/, far_clip);
4 = normalized perspective with near clip = 0.001 gluPerspective(lens_angle, 1.0, 0.001/*near_clip*/, far_clip);

viewalign[int]

View aligned transformation flag (default = 0)

Common Box Attributes

Below is a list of attributes shared by all objects. If you want to change one of these attributes for an object based on the object box, you need to place the word sendbox in front of the attribute name, or use the object's Inspector.

annotation[symbol]

Sets the text that will be displayed in the Clue window when the user moves the mouse over the object.

background[int]: 0

Adds or removes the object from the patcher's background layer. background 1 adds the object to the background layer, background 0 removes it. Objects in the background layer are shown behind all objects in the default foreground layer.

color[4 floats]

Sets the color for the object box outline.

fontface[int]

Sets the type style used by the object. The options are:

plain
bold
italic
bold italic Possible values:

0 = 'regular'
1 = 'bold'
2 = 'italic'
3 = 'bold italic'

fontname[symbol]

Sets the object's font.

fontsize[float]

Sets the object's font size (in points). Possible values:

'8'
'9'
'10'
'11'
'12'
'13'
'14'
'16'
'18'
'20'
'24'
'30'
'36'
'48'
'64'
'72'

hidden[int]: 0

Toggles whether an object is hidden when the patcher is locked.

hint[symbol]

Sets the text that will be displayed in as a pop-up hint when the user moves the mouse over the object in a locked patcher.

ignoreclick[int]: 0

Toggles whether an object ignores mouse clicks in a locked patcher.

jspainterfile[symbol]

You can override the default appearance of a user interface object by assigning a JavaScript file with code for painting the object. The file must be in the search path.

patching_rect[4 floats]: 0. 0. 100. 0.

Sets the position and size of the object in the patcher window.

position[2 floats]
write-only

Sets the object's x and y position in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its size unchanged.

presentation[int]: 0

Sets whether an object belongs to the patcher's presentation.

presentation_rect[4 floats]: 0. 0. 0. 0.

Sets the x and y position and width and height of the object in the patcher's presentation, leaving its patching position unchanged.

rect[4 floats]
write-only

Sets the x and y position and width and height of the object in both patching and presentation modes (if the object belongs to its patcher's presentation).

size[2 floats]
write-only

Sets the object's width and height in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its position unchanged.

textcolor[4 floats]

Sets the color for the object's text in RGBA format.

textjustification[int]

Sets the justification for the object's text. Possible values:

0 = 'left'
1 = 'center'
2 = 'right'

varname[symbol]

Sets the patcher's scripting name, which can be used to address the object by name in pattr, scripting messages to thispatcher, and the js object.

Messages

int

Send an int to the msg_int function.

float

Send an int to the msg_float function.

list

Send an int to the msg_list function.

anything

Call a function with arbitrary arguments.

call

Explicitly call a function with arbitrary arguments.

closebang

When the closebang message is triggered, jit.gl.lua will look for a closebang() function in the currently running Lua script and call it.

(mouse)

Double-click to open Lua editing window

loadbang

When the loadbang message is triggered, jit.gl.lua will look for a loadbang() function in the currently running Lua script and call it.

open

Opens the text window where the object's Lua source file can be edited.

read

Read a Lua script

wclose

Closes the text window where the object's Lua source file is edited.

OB3D Messages

bang

Equivalent to the draw message.

draw

Draws the object in the named drawing destination. If the matrixoutput attribute is supported and set to 1, the geometry matrices are sent out the object's left outlet.

drawraw

Equivalent to draw with the inherit_all attribute set to 1.

drawimmediate

Equivalent to draw but ignoring any potential renderer setup

anim_move

Move the object along the axis provided, relative to the space indicated by animmode.

Arguments:
  • x [float]
  • y [float]
  • z [float]

anim_turn

Rotate the object along each axis by the amount provided, relative to the space indicated by animmode.

Arguments:
  • x [float]
  • y [float]
  • z [float]

anim_grow

Scale the object along each axis by the amount provided.

Arguments:
  • x [float]
  • y [float]
  • z [float]

anim_reset

Reset the local transformation attributes to their default values (position = 0 0 0, rotatexyz = 0 0 0, and scale = 1 1 1)

update_node

Update the node transformation attributes.

import_material

Import a Jitter material file (.jitmtl).

export_material

Export material state as a material file (.jitmtl).

jit_gl_texture

Binds the texture specified by texture-name to this object. Equivalent to setting the texture attribute to texture-name .

Arguments:
  • texture-name [symbol]

get_shader

Open an editor window containing the object's current JXS shader.

export_geometry

Export the object's geometry state as model file with the name specified by the first argument. The second argument sets the file type (default = gltf). Available file types are gltf (GL Transmission Format), ply (Stanford Polygon Library), and stl (Stereolithography).

Arguments:
  • filename [symbol]
  • file-type [symbol]

See Also

Name Description
jit.gl.lua Color Bindings jit.gl.lua Color Bindings
jit.gl.lua OpenGL Bindings jit.gl.lua OpenGL Bindings
jit.gl.lua Overview jit.gl.lua Overview
jit.gl.lua Vector Math jit.gl.lua Vector Math
js Execute Javascript (Legacy Engine)
jit.gl.sketch Use drawing commands with OpenGL