From 7b52cc13af4e85f1ca2deb6b6c77de9c95ea0dcf Mon Sep 17 00:00:00 2001 From: scuri Date: Fri, 17 Oct 2008 06:10:33 +0000 Subject: First commit - moving from LuaForge to SourceForge --- html/en/func/filled.html | 272 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 272 insertions(+) create mode 100644 html/en/func/filled.html (limited to 'html/en/func/filled.html') diff --git a/html/en/func/filled.html b/html/en/func/filled.html new file mode 100644 index 0000000..2ae1083 --- /dev/null +++ b/html/en/func/filled.html @@ -0,0 +1,272 @@ + + + + + + +Filled Areas + + + + + +

Filled Areas

+ +

It is an area filled with the foreground color, but it depends on the + current interior style. The SOLID style + depends only on the foreground color. The HATCH + and + STIPPLE style depend on the foreground color, background color and on the back opacity attribute. The + hatch lines drawn with this style do not depend on the other line attributes. The + PATTERN style depends only on global canvas + attributes.

+

The filled area includes the line at the edge of the area. So if you draw a +filled rectangle, sector or polygon on top of a non filled one using the same +coordinates, no style and 1 pixel width, the non filled primitive should be +obscured by the filled primitive. But depending on the driver implementation +some pixels at the edges may be not included. IMPORTANT: In the Postscript and +PDF drivers the line at the edge is not included at all.

+

If + either the background or the foreground color are modified, the hatched and + monochromatic fillings must be modified again in order to be updated.

+

Note that when a Filling Attribute is modified, the active filling style is + now that of the modified attribute (hatch, stipple or pattern). Notice that + this is not true for the clipping area. When the clipping area is modified, + the clipping is only affected if it is active.

+ +
+
Filled Polygons
+ +

Filled polygons can be created using cdBegin(CD_FILL)/cdVertex(x,y)/.../cdEnd().

+

See the documentation of cdBegin/cdVertex/cdEnd.

+ +
void cdCanvasBox(cdCanvas* canvas, int xmin, int xmax, int ymin, int ymax); [in C]
+void cdfCanvasBox(cdCanvas* canvas, double xmin, double xmax, double ymin, double ymax); [in C]
+void wdCanvasBox(cdCanvas* canvas, double xmin, double xmax, double ymin, double ymax); (WC) [in C]
+
+canvas:Box(xmin, xmax, ymin, ymax: number) [in Lua]
+canvas:fBox(xmin, xmax, ymin, ymax: number) [in Lua]
+canvas:wBox(xmin, xmax, ymin, ymax: number) (WC) [in Lua]
+ +

Fills a rectangle according to the current interior style. All points in + the interval x_min<=x<=x_max, y_min<=y<=y_max + will be painted. When the interior style CD_HOLLOW + is defined, the function behaves like its equivalent + cdRect.

+ +
void cdCanvasSector(cdCanvas* canvas, int xc, int yc, int w, int h, double angle1, double angle2); [in C]
+void cdfCanvasSector(cdCanvas* canvas, double xc, double yc, double w, double h, double angle1, double angle2); [in C]
+void wdCanvasSector(cdCanvas* canvas, double xc, double yc, double w, double h, double angle1, double angle2); (WC) [in C]
+
+canvas:Sector(xc, yc, w, h, angle1, angle2: number) [in Lua]
+canvas:fSector(xc, yc, w, h, angle1, angle2: number) [in Lua]
+canvas:wSector(xc, yc, w, h, angle1, angle2: number) (WC) [in Lua]
+ +

Fills the arc of an ellipse aligned with the axis, according to the current + interior style, in the shape of a pie. It is drawn counter-clockwise. The + coordinate (xc,yc) defines the center of the ellipse. + Dimensions w and h define the elliptic axes X + and Y, respectively.

+

Angles angle1 and angle2, in degrees, + define the arc's beginning and end, but they are not the angle relative to the + center, except when w==h and the ellipse is reduced to a circle. The arc + starts at the point (xc+(w/2)*cos(angle1),yc+(h/2)*sin(angle1)) + and ends at (xc+(w/2)*cos(angle2),yc+(h/2)*sin(angle2)). A + complete ellipse can be drawn using 0 and 360 as the angles.

+

The angles are specified so if the size of the ellipse (w x h) is changed, + its shape is preserved. So the angles relative to the center are dependent + from the ellipse size. The actual angle can be obtained using rangle = + atan2((h/2)*sin(angle),(w/2)*cos(angle)).

+

The angles are given in degrees. To specify the angle in radians, you can + use the definition CD_RAD2DEG + to multiply the value in radians before passing the angle to CD.

+

When the interior style CD_HOLLOW is defined, + the function behaves like its equivalent cdArc, + plus two lines connecting to the center.

+

Sector Parameters
+

+ +
void cdCanvasChord(cdCanvas* canvas, int xc, int yc, int w, int h, double angle1, double angle2); [in C]
+void cdfCanvasChord(cdCanvas* canvas, double xc, double yc, double w, double h, double angle1, double angle2); [in C]
+void wdCanvasChord(cdCanvas* canvas, double xc, double yc, double w, double h, double angle1, double angle2); (WC) [in C]
+
+canvas:Chord(xc, yc, w, h, angle1, angle2: number) [in Lua]
+canvas:fChord(xc, yc, w, h, angle1, angle2: number) [in Lua]
+canvas:wChord(xc, yc, w, h, angle1, angle2: number) (WC) [in Lua]
+ +

Fills the arc of an ellipse aligned with the axis, according to the current + interior style, the start and end points of the arc are connected. The + parameters are the same as the cdSector.

+

When the interior style CD_HOLLOW is defined, + the function behaves like its equivalent cdArc, + plus a line connecting the arc start and end points.

+

Chord Parameters
+

+ +

Attributes

+
int cdCanvasBackOpacity(cdCanvas* canvas, int opacity); [in C]
+
+canvas:BackOpacity(opacity: number) -> (old_opacity: number) [in Lua]
+ +

Configures the background opacity to filling primitives based on the + foreground and background colors. Values: + CD_TRANSPARENT or CD_OPAQUE. If it is opaque + the primitive will erase whatever is in background with the background color. + If it is transparent, only the foreground color is painted. It returns the previous value. Default value: + CD_TRANSPARENT. Value CD_QUERY simply returns the + current value. In some drivers is always opaque.

+

Back Opacity Attribute
+

+ +
int cdCanvasFillMode(cdCanvas* canvas, int mode); [in C]
+
+canvas:FillMode(mode: number) -> (old_mode: number) [in Lua]
+ +

Selects a predefined polygon fill rule (CD_EVENODD or CD_WINDING). Returns the previous value. Default value: + CD_EVENODD. Value CD_QUERY simply returns the current + value.

+

Fill Modes
+

+ +
int cdCanvasInteriorStyle(cdCanvas* canvas, int style); [in C]
+
+canvas:InteriorStyle(style: number) -> (old_style: number) [in Lua]
+ +

Configures the current style for the area filling primitives: + CD_SOLID, CD_HOLLOW, CD_HATCH, + CD_STIPPLE or CD_PATTERN. Note that + CD_HATCH and CD_STIPPLE are affected by the backopacity. It returns the previous value. Default value: CD_SOLID. Value + CD_QUERY simply returns the + current value.

+

If a stipple or a pattern were not defined, when they are + selected the state of the + attribute is not changed.

+

When the style CD_HOLLOW is defined, functions + cdBox and cdSector behave as their + equivalent cdRect and cdArc+Lines, and the + polygons with style CD_FILL behave like CD_CLOSED_LINES.

+ +
int cdCanvasHatch(cdCanvas* canvas, int style); [in C]
+
+canvas:Hatch(style: number) -> (old_style: number) [in Lua]
+ +

Selects a predefined hatch style (CD_HORIZONTAL, CD_VERTICAL, + CD_FDIAGONAL, CD_BDIAGONAL, + CD_CROSS or CD_DIAGCROSS) and sets the + interior style to CD_HATCH. The lines are drawn with the foreground + color, and the background is drawn with the background color if back opacity + is opaque. Returns the previous value. + Default value: CD_HORIZONTAL. Value CD_QUERY + simply returns the current value. The foreground and background colors must be + set before setting the style. In some drivers is always opaque.

+

Hatch Styles
+

+ +
void cdCanvasStipple(cdCanvas* canvas, int w, int h, const unsigned char *fgbg) [in C]
+
+canvas:Stipple(stipple: cdStipple) [in Lua]
+ +

Defines a wxh matrix of zeros (0) and ones (1). The zeros are + mapped to the background color or are transparent, according to the background + opacity attribute. The ones are mapped to the foreground color. The function + sets the interior style to CD_STIPPLE. To avoid having to deal + with matrices in C, the element (i,j) of fgbg + is stored as fgbg[j*w+i]. The origin is the left bottom corner + of the image. It does not need to be stored by the + application, as it is internally replicated by the library.  In some + drivers is always opaque. The foreground and background colors must be set + before setting the style.

+ +
void wdCanvasStipple(cdCanvas* canvas, int w, int h, const unsigned char *fgbg, double w_mm, double h_mm); [in C]
+
+canvas:wStipple(stipple: cdStipple, w_mm, h_mm: number) [in Lua]
+ +

Allows specifying the stipple in world coordinates. Another stipple will be + created with the size in pixels corresponding to the specified size in + millimeters. The new size in pixels will be an integer factor of the original + size that is closets to the size in millimeters. The use of this function may produce very large or very small + stipples.

+ +
unsigned char* cdCanvasGetStipple(cdCanvas* canvas, int* w, int* h); [in C]
+
+canvas:GetStipple() - > (stipple: cdStipple) [in Lua]
+ +

Returns the current stipple and its dimensions. Returns NULL if no + stipple was defined.

+ +
void cdCanvasPattern(cdCanvas* canvas, int w, int h, const long int *color); [in C]
+
+canvas:Pattern(pattern: cdPattern) [in Lua]
+ +

Defines a new wxh color matrix and sets the interior style + to CD_PATTERN. To avoid having to deal with matrices in C, the + color element (i,j) is stored as color[j*w+i]. + The origin is the left bottom corner of the image. It + does not need to be stored by the application, as it is internally replicated + by the library.

+ +
void wdCanvasPattern(cdCanvas* canvas, int w, int h, const long int *color, double w_mm, double h_mm); [in C]
+
+canvas:wPattern(pattern: cdPattern, w_mm, h_mm: number) [in Lua]
+ +

Allows specifying the pattern in world coordinates. Another pattern will be + created with the size in pixels corresponding to the specified size in + millimeters. The new size in pixels will be an integer factor of the original + size that is closets to the size in millimeters. The use of this function may produce very large or very small + patterns.

+ +
long int* cdCanvasGetPattern(cdCanvas* canvas, int* w, int* h); [in C]
+
+canvas:GetPattern() - > (pattern: cdPattern) [in Lua]
+ +

Returns the current pattern and its dimensions. Returns NULL if no + pattern was defined.

+ +

Extras in Lua

+
cd.CreatePattern(width, height: number) -> (pattern: cdPattern)
+ +

Creates a pattern in Lua.

+ +
cd.KillPattern(pattern: cdPattern)
+ +

Destroys the created pattern and liberates allocated memory. If this + function is not called in Lua, the garbage collector will call it.

+ +
cd.CreateStipple(width, height: number) -> (stipple: cdStipple)
+ +

Creates a stipple in Lua.

+ +
cd.KillStipple(stipple: cdStipple)
+ +

Destroys the created stipple and liberates allocated memory. If this + function is not called in Lua, the garbage collector will call it.

+ +

Data Access

+ +

Data access in Lua is done directly using the operator "[y*width + + x]".

+

All new types can have their values checked or changed directly as if they + were Lua tables:

+ + 
pattern[y*16 + x] = cd.EncodeColor(r, g, b)
+...
+color = pattern[y*16 + x]
+r, g, b = cd.DecodeColor(color)
+...
+cd.Pattern(pattern)
+ +

Notice that the type of value returned or received by + pattern[i] is a + lightuserdata, the same type used with functions + cdEncodeColor, + cdDecodeColor, + cdPixel, + cdForeground + and cdBackground. The value + returned or received by stipple[i] + is a number.

+ + + + + \ No newline at end of file -- cgit v1.2.3