cdCanvas *cdCreateCanvas(cdContext* ctx, void *data); [in C]
cd.CreateCanvas(ctx: number, data: string or userdata) -> (canvas: cdCanvas) [in Lua]
Creates a CD canvas for a virtual visualization surface (VVS). A VVS may be the canvas of a user-interface window, the page of a document sent to a printer, an offscreen image, the clipboard, a metafile, and so on. To create the canvas, it is necessary to specify the driver in which each canvas is implemented.
The driver is set by the driver variable with additional information provided in the data parameter. Even though it is possible to create more than one canvas with the same driver/data pair, this is not recommended, and its behavior is not specified. Each canvas maintains its own features.
In case of failure, a NULL value is returned. The following predefined drivers are available:
Window-Base Drivers
Device-Based Drivers
Image-Based Drivers
File-Based Drivers
cdCanvas* cdCreateCanvasf(cdContext *ctx, const char* format, ...); [in C]
[There is no equivalent in Lua]
Same as cdCreateCanvas, used in the case that the parameter data is a string composed by several parameters. This function can be used with parameters equivalent to the printf function from the default C library.
void cdKillCanvas(cdCanvas *canvas); [in C]
cd.KillCanvas(canvas: cdCanvas) [in Lua]
Destroys a previously created canvas. If this function is not called in Lua, the garbage collector will call it.
int cdCanvasActivate(cdCanvas *canvas); [in C]
canvas:Activate(canvas: cdCanvas) -> (status: number) [in Lua]
Activates a canvas for drawing. This is used only for a few drivers. Native Window and IUP drivers will update the canvas size if the window size has changed. Double Buffer driver will recreate the image buffer if the window canvas size has changed. In these cases the function MUST be called, for other drivers is useless. Returns CD_ERROR or CD_OK.
void cdCanvasDeactivate(cdCanvas* canvas); [in C]
canvas:Deactivate(canvas: cdCanvas) [in Lua]
Called when the application has finished drawing in the canvas. It is optional, but if used for the Native Window driver in Windows when the handle can not be retained, the drawing can only be done again after a cdCanvasActivate. On some drivers will simply call Flush.
int cdUseContextPlus(int use); [in C]
cd.UseContextPlus(use: boolean) -> (old_use: boolean) [in Lua]
Activates or deactivates the use of an external context for the next calls of the cdCreateCanvas function.
void cdInitContextPlus(void); [in C]
cd.InitContextPlus() [in Lua]
Initializes the context driver to use another context replacing the standard drivers. This functions is only available when a library containing a "ContextPlus" context driver is used. See the Cairo, Direct2D, GDI+ and XRender base drivers. Those libraries does not support XOR write mode, but has support for anti-aliasing and alpha for transparency.
In Lua, when using require"cdluacontextplus" this function will be automatically called.
cdContext* cdCanvasGetContext(cdCanvas *canvas); [in C]
canvas:GetContext(canvas: cdCanvas) -> (ctx: number) [in Lua]
Returns the context of a given canvas, which can be compared with the predefined contexts, such as "CD_PS".
int cdContextCaps(cdContext* ctx); [in C]
cd.ContextCaps(ctx: number) -> (caps: number) [in Lua]
Returns the resources available for that context. To verify if a given resource is available, perform a binary AND with the following values:
CD_CAP_FLUSH CD_CAP_CLEAR CD_CAP_PLAY CD_CAP_YAXIS - The native Y axis orientation is bottom-up. CD_CAP_CLIPAREA CD_CAP_CLIPPOLY - Usually is not implemented. CD_CAP_REGION - Usually is not implemented. CD_CAP_RECT - Rectangles are implemented directly in the driver (they are usually simulated). CD_CAP_CHORD CD_CAP_IMAGERGB CD_CAP_IMAGERGBA - If this is not implemented, but cdGetImageRGB is, then it is simulated using cdGetImageRGB and cdPutImageRGB. CD_CAP_IMAGEMAP CD_CAP_GETIMAGERGB CD_CAP_IMAGESRV - Usually is only implemented in contexts of window graphics systems (Native Window and IUP). CD_CAP_BACKGROUND CD_CAP_BACKOPACITY CD_CAP_WRITEMODE CD_CAP_LINESTYLE CD_CAP_LINEWITH CD_CAP_FPRIMTIVES - Primitives using floatig point coordinates are implemented directly in the driver (they are usually simulated). CD_CAP_HATCH CD_CAP_STIPPLE CD_CAP_PATTERN CD_CAP_FONT CD_CAP_FONTDIM - If not defined, the function is implemented using an internal heuristics of the library. CD_CAP_TEXTSIZE - If not defined, the function is implemented using an internal heuristics of the library. CD_CAP_TEXTORIENTATION - Usually is not implemented. CD_CAP_PALETTE - Usually is only implemented in contexts of window graphics systems (Native Window and IUP). CD_CAP_LINECAP CD_CAP_LINEJOIN CD_CAP_PATH CD_CAP_BEZIER
int cdContextType(cdContext* ctx); [in C]
cd.ContextType(ctx: number) -> (type: number) [in Lua]
Returns the type of the context:
CD_CTX_WINDOW - GUI window based CD_CTX_DEVICE - device based (clipboard, printer, picture) CD_CTX_IMAGE - server or client image based, including double buffer based CD_CTX_FILE - metafile based
int cdContextIsPlus(cdContext* ctx); [in C]
cd.ContextIsPlus(ctx: number) -> (plus: boolean) [in Lua]
Returns if it is a context plus.
int cdCanvasSimulate(cdCanvas* canvas, int mode); [in C]
canvas:Simulate(mode: number) -> (old_mode: number) [in Lua]
Activates the simulation of one or more primitives. It is ignored for the canvas in the ImageRGB context, because in this case everything is already simulated. It also has no effect for primitives that are usually simulated. It returns the previous simulation, but does not include primitives that are usually simulated. The simulation can be activated at any moment. For instance, if a line simulation is required only for a situation, the simulation can be activated for the line to be drawn, and then deactivated.
If simulation is activated the driver transformation matrix is disabled.
See in the Simulation sub-driver the information on how each simulation is performed.
To activate a given simulation, perform a binary OR ('|.html using one or more of the following values (in Lua, the values must be added '+.html:
CD_SIM_NONE - Deactivates all kinds of simulation. CD_SIM_LINE CD_SIM_RECT CD_SIM_BOX CD_SIM_ARC CD_SIM_SECTOR CD_SIM_CHORD CD_SIM_POLYLINE CD_SIM_POLYGON CD_SIM_TEXT CD_SIM_ALL - Activates all simulation options. CD_SIM_LINES - Combination of CD_SIM_LINE, CD_SIM_RECT, CD_SIM_ARC and CD_SIM_POLYLINE. CD_SIM_FILLS - Combination of CD_SIM_BOX, CD_SIM_SECTOR, CD_SIM_CHORD and CD_SIM_POLYGON.
int cdlua_open(lua_State* L); [for Lua 5]
Initializes the CDLua binding. In Lua 5 the binding is lua state safe, this means that several states can be initialized any time.
int cdlua_close(lua_State* L); [for Lua 5]
cd.Close() [in Lua]
Releases the memory allocated by the CDLua binding.
cdCanvas* cdlua_checkcanvas(lua_State* L, int pos); [for Lua 5]
Returns the canvas in the Lua stack at position pos. The function will call lua_error if there is not a valid canvas in the stack at the given position.
void cdlua_pushcanvas(lua_State* L, cdCanvas* canvas);
Pushes the given canvas into the stack.