LuaGL
OpenGL binding for Lua 5.1
Based on http://luagl.sourceforge.net

whatis · portability · download · how it works · reference ·


What is it LuaGL?

It’s a library that provides access to all of the OpenGL functionality from Lua.

What is OpenGL?

OpenGL is a portable software interface to graphics hardware. More information about OpenGL can be obtained from http://www.opengl.org. You can find good tutorials about learning OpenGL at http://nehe.gamedev.net.

Portability

That library should run in all systems that support OpenGL.

License

LuaGL is a free software and uses the MIT License. It can be used at no cost for both academic and commercial purposes.

Download & Installation

You can download LuaGL from the sourceforge project home page here (OLD version only).

LuaGL also needs that you have the OpenGL library installed. All modern operating systems already have it, see OpenGL Platform & OS Implementations.

Authors

Changes from LuaGL in SourceForge

Changes by Antonio Scuri.

To do: change error handling to use luaL_check* functions.

How it works ?

This library works as a binding for all OpenGL commands, so you can have full access to the graphics hardware from Lua.

To have access to the library from a C host program, you must first call the 'luaopen_gl' function. To have access from Lua, simply call require"luagl".

This will create a name space called 'gl', and all the functions and constants will be inside of it.

OpenGL constants

All OpenGL constants were converted to strings, for example: instead of writing GL_QUADS, you should write 'QUADS'. In functions that expected a bitwise operation between mask parameters, in Lua will receive a string that contains all the constants strings separated by comma (,). For example:

gl.Begin("TRIANGLES")
gl.Clear('COLOR_BUFFER_BIT,DEPTH_BUFFER_BIT') 

OpenGL constants can also be used as numbers using gl.XXX notation, where XXX is the constant name after "GL" (for example: gl.QUADS). This is much faster than using the strings.

Argument specification

The argument specification (e.g., '2d', '3f', '4sv') at the end of most OpenGL functions names have been removed. For example the new gl.Light function binds the OpenGL functions: glLightf, glLightfv, glLighti, glLightiv.

It’s always used the floating point version of the functions, with the highest possible precision.

Color and Vector data

The color and the vector data can be represented by a lua array. A vector can have 2, 3 or 4 values (x, y, z, w), and colors can have 3 or 4 values (red, green, blue, alpha). If there are more 4 value the extra parameters will be ignored.

For example:

v1 = { 0, 0 } 
v2 = { 1, 1 } 
Yellow = { 1, 1, 0 } 
gl.Color(Yellow) 
gl.Vertex(v1) 
gl.Vertex(v2) 

you can also call those:

gl.Color(1, 1, 0) 
gl.Vertex(0, 0) 
gl.Vertex(1, 1) 

Argument types

The OpenGL function parameters that specify the type of another argument, or the size of an array, won’t be used. Lua will always use the most precise type of data. The stride value of an array won’t be used too. For example:

gl.VertexPointer(vertex_array) 

binds:

void glVertexPointer (GLint size, GLenum type, GLsizei stride, const GLvoid *pointer); 

Where ‘vertex_array’ is an array of vectors. The size of the array returned by lua_getn function will be used as the size parameter. The type is the most precise possible, and the stride value is always set to zero. You can see an example of this function bellow:

v1 = { -1, -1 } 
v2 = {  1, -1 } 
v3 = {  1,  1 } 
v4 = { -1,  1 } 

vertices  = { v1, v2, v3, v4 } 

gl.VertexPointer(vertices) 

Requesting OpenGL information

The functions that request information from OpenGL, will now return the data by the function return value, instead of returning by a parameter. For example:

image = gl.GetTexImage (target, level, format) 

For more information about functions names and parameters, see the Function Reference bellow.

Bit Pattern

Functions that expects a number with a bit pattern, will accept a string with the mask numbers. All characters that are different to ‘0’ and ‘1’ will be ignored. For example:

gl.LineStipple (1, "1111000011110000") 
gl.LineStipple (1, "1010.0101.1000.1111" ) 
gl.LineStipple (1, "0000 0000 1111 1111" ) 

Function Reference

Accum (op, value) -> none 

AlphaFunc (func, ref) -> none 

AreTexturesResident (texturesArray) -> residences 

ArrayElement (i) -> none 

Begin (mode) -> none 

BindTexture (target, texture) -> none 

Bitmap (xorig, yorig, ymove, bitmap) -> none 

BlendFunc (sfactor, dfactor) -> none 

CallList (list) -> none 

CallLists (listArray) -> none 

Clear (mask) -> none 

ClearAccum (red, green, blue, alpha) -> none 

ClearColor (red, green, blue, alpha) -> none 

ClearDepth (depth) -> none 

ClearIndex (c) -> none 

ClearStencil (s) -> none 

ClipPlane (plane, equationArray) -> none 

Color (red, green, blue [, alpha]) -> none 
Color (color) -> none 

ColorMask (red, green, blue, alpha) -> none 

ColorMaterial (face, mode) -> none 

ColorPointer (colorArray) -> none 

CopyPixels (x, y, width, height, type) -> none 

CopyTexImage (level, internalFormat, border, x, y, width[, height]) -> none 

CopyTexSubImage (level, x, y, xoffset, width[, yoffset, height]) -> none 

CullFace (mode) -> none 

DeleteLists (list, range) -> none 

DeleteTextures (texturesArray) -> none 

DepthFunc (func) -> none 

DepthMask (flag) -> none 

DepthRange (zNear, zFar) -> none 

Disable (cap) -> none 

DisableClientState (array) -> none 

DrawArrays (mode, first, count) -> none 

DrawBuffer (mode) -> none 

DrawElements (mode, indicesArray) -> none 

DrawPixels (width, height, format, pixels) -> none 

EdgeFlag (flag) -> none 

EdgeFlagPointer (flagsArray) -> none 

Enable (cap) -> none 

EnableClientState (array) -> none 

End () -> none 

EndList () -> none 

EvalCoord (u[, v]) -> none 
EvalCoord (coordArray) -> none 

EvalMesh (mode, i1, i2[,j1, j2]) -> none 

EvalPoint (i[, j]) -> none 

FeedbackBuffer (size, type) -> dataArray 

Finish () -> none 

Flush () -> none 

Fog (pname, param) -> none 
Fog (pname, paramsArray) -> none 

FrontFace (mode) -> none 

Frustum (left, right, bottom, top, zNear, zFar) -> none 

GenLists (range) -> num 

GenTextures (n) -> texturesArray 

Get (pname) -> params 

GetArray (pname) -> paramsArray 

GetConst (pname) -> constant string 

GetClipPlane (plane) -> equationArray 

GetError () -> error flag 

GetLight (light, pname) -> paramsArray 

GetMap (target, query) -> vArray 

GetMaterial (face, pname) -> paramsArray 

GetPixelMap (map) -> valuesArray 

GetPointer (pname, n) -> valuesArray 

GetPolygonStipple () -> maskArray 

GetString (name) -> string 

GetTexEnv (pname) -> paramsArray 

GetTexGen (coord, pname) -> paramsArray 

GetTexImage (target, level, format) -> pixelsArray 

GetTexLevelParameter (target, level, pname) -> param 

GetTexParameter (target, pname) -> paramsArray 

Hint (target, mode) -> none 

Index (c) -> none 

IndexMask (mask) -> none 

IndexPointer (indexArray) -> none 

InitNames () -> none 

InterleavedArrays (format, dataArray) -> none 

IsEnabled (cap) -> true/false 

IsList (list) -> true/false 

IsTexture (texture) -> true/false 

Light (light, pname, param) -> none 
Light (light, pname, paramsArray) -> none 

LightModel (pname, param) -> none 
LightModel (pname, paramsArray) -> none 

LineStipple (factor, pattern) -> none 

LineWidth (width) -> none 

ListBase (base) -> none 

LoadIdentity () -> none 

LoadMatrix (mArray) -> none 

LoadName (name) -> none 

LogicOp (opcode) -> none 

Map (target, u1, u2, ustride, pointsArray) -> none 
Map (target, u1, u2, ustride, v1, v2, vstride, pointsArray) -> none 

MapGrid (un, u1, u2[, vn, v1, v2]) -> none 

Material (face, pname, param) -> none 

MatrixMode (mode) -> none 

MultMatrix (mArray) -> none 

NewList (list, mode) -> none 

Normal (nx, ny, nz) -> none 
Normal (nArray) -> none 

NormalPointer (normalArray) -> none 

Ortho (left, right, bottom, top, zNear, zFar) -> none 

PassThrough (token) -> none 

PixelMap (map, valuesArray) -> none 

PixelStore (pname, param) -> none 

PixelTransfer (pname, param) -> none 

PixelZoom (xfactor, yfactor) -> none 

PointSize (size) -> none 

PolygonMode (face, mode) -> none 

PolygonOffset (factor, units) -> none 

PolygonStipple (maskArray) -> none 

PopAttrib () -> none 

PopClientAttrib () -> none 

PopMatrix () -> none 

PopName () -> none 

PrioritizeTextures (texturesArray, prioritiesArray) -> none 

PushAttrib (mask) -> none 

PushClientAttrib (mask) -> none 

PushMatrix () -> none 

PushName (GLuint name) -> none 

RasterPos (x, y[, z, w]) -> none 
RasterPos (vArray) -> none 

ReadBuffer (mode) -> none 

ReadPixels (x, y, width, height, format, pixelsArray) -> none 

Rect (x1, y1, x2, y2) -> none 
Rect (v1, v2) -> none 

RenderMode (mode) -> none 

Rotate (angle, x, y, z) -> none 

Scale (x, y, z) -> none 

Scissor (x, y, width, height) -> none 

SelectBuffer (size) -> SelectArray 

ShadeModel (mode) -> none 

StencilFunc (func, ref, mask) -> none 

StencilMask (mask) -> none 

StencilOp (fail, zfail, zpass) -> none 

TexCoord (s[, t, r, q]) -> none 
TexCoord (vArray) -> none 

TexCoordPointer(vArray) -> none 

TexEnv (pname, param) -> none 
TexEnv (pname, paramsArray) -> none 

TexGen (coord, pname, param) -> none 
TexGen (coord, pname, paramsArray) -> none 

TexImage(level, internalformat, format, pixels) -> none 

TexParameter (target, pname, param) -> none 
TexParameter (target, pname, paramsArray) -> none 

TexSubImage (level, format, pixels, xoffset) -> none 
TexSubImage (level, format, pixels, xoffset, yoffset) -> none 

Translate (x, y, z) -> none 

Vertex (x, y, [z, w]) -> none 
Vertex (vArray) -> none 

VertexPointer (vertexArray) -> none 

VViewport (x, y, width, height) -> none