General drawing functions

Modules
	Advanced 2-Dimension graphics functions.

Macros
#define	DrawHDotLine(hdc, x, y, w)   DrawHVDotLine (hdc, x, y, w, TRUE);
	Draws a horizontal dot dash line. More...
#define	DrawVDotLine(hdc, x, y, h)   DrawHVDotLine (hdc, x, y, h, FALSE);
	Draws a vertical dot line. More...
#define	PolygonGenerator(context, pts, vertices, cb)   PolygonGeneratorEx(context, pts, vertices, cb, NULL)
	This is a general polygon generator. More...

Typedefs
typedef void(*	CB_LINE) (void *context, int stepx, int stepy)
	The type of line generator callback. More...
typedef void(*	CB_CIRCLE) (void *context, int x1, int x2, int y)
	The type of circle generator callback. More...
typedef void(*	CB_ELLIPSE) (void *context, int x1, int x2, int y)
	The type of ellipse generator callback. More...
typedef void(*	CB_ARC) (void *context, int x, int y)
	The type of arc generator callback. More...
typedef void(*	CB_POLYGON) (void *context, int x1, int x2, int y)
	The type of polygon generator callback. More...
typedef BOOL(*	CB_EQUAL_PIXEL) (void *context, int x, int y)
	Flodd filling generator's equation callback. More...
typedef void(*	CB_FLOOD_FILL) (void *context, int x1, int x2, int y)
	Flodd filling generator's scan line callback. More...

Functions
MG_EXPORT void GUIAPI	SetPixel (HDC hdc, int x, int y, gal_pixel pixel)
	Sets the pixel with a new pixel value at the specified position on a DC. More...
MG_EXPORT gal_pixel GUIAPI	SetPixelRGB (HDC hdc, int x, int y, Uint8 r, Uint8 g, Uint8 b)
	Sets the pixel by a RGB triple at the specified position on a DC. More...
MG_EXPORT gal_pixel GUIAPI	SetPixelRGBA (HDC hdc, int x, int y, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
	Sets the pixel by a RGBA quarter at the specified position on a DC. More...
MG_EXPORT gal_pixel GUIAPI	GetPixel (HDC hdc, int x, int y)
	Gets the pixel value at the specified position on a DC. More...
MG_EXPORT gal_pixel GUIAPI	GetPixelRGB (HDC hdc, int x, int y, Uint8 *r, Uint8 *g, Uint8 *b)
	Gets the pixel value at the specified position on a DC in RGB triple. More...
MG_EXPORT gal_pixel GUIAPI	GetPixelRGBA (HDC hdc, int x, int y, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a)
	Gets the pixel value at the specified position on a DC in RGBA quarter. More...
MG_EXPORT void GUIAPI	RGBA2Pixels (HDC hdc, const RGB *rgbs, gal_pixel *pixels, int count)
	Gets the pixel values from a color array in RGBA quarter under a DC. More...
static gal_pixel	RGBA2Pixel (HDC hdc, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
	Gets the pixel value from a color in RGBA quarter under a DC. More...
MG_EXPORT void GUIAPI	RGB2Pixels (HDC hdc, const RGB *rgbs, gal_pixel *pixels, int count)
	Gets the pixel values from a color array in RGB triple under a DC. More...
static gal_pixel	RGB2Pixel (HDC hdc, Uint8 r, Uint8 g, Uint8 b)
	Gets the pixel value from a color in RGB triple under a DC. More...
MG_EXPORT void GUIAPI	Pixel2RGBs (HDC hdc, const gal_pixel *pixels, RGB *rgbs, int count)
	Gets the colors in RGB triple from a pixel value array under a DC. More...
static void	Pixel2RGB (HDC hdc, gal_pixel pixel, Uint8 *r, Uint8 *g, Uint8 *b)
	Gets the color in RGB triple from a pixel value under a DC. More...
MG_EXPORT void GUIAPI	Pixel2RGBAs (HDC hdc, const gal_pixel *pixels, RGB *rgbs, int count)
	Gets the colors in RGBA quarter from a array of pixel values under a DC. More...
static void	Pixel2RGBA (HDC hdc, gal_pixel pixel, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a)
	Gets the color in RGBA quarter from a pixel value under a DC. More...
static DWORD	Pixel2DWORD (HDC hdc, gal_pixel pixel)
	An inline function to convert pixel value to DWORD color. More...
static gal_pixel	DWORD2Pixel (HDC hdc, DWORD dword)
	An inline function to convert DWORD color to gal_pixel. More...
MG_EXPORT void GUIAPI	FocusRect (HDC hdc, int x0, int y0, int x1, int y1)
	Draws a focus rectangle. More...
MG_EXPORT void GUIAPI	DrawHVDotLine (HDC hdc, int x, int y, int w_h, BOOL H_V)
	Draws a horizontal or vertical dot dash line. More...
MG_EXPORT BOOL GUIAPI	LineClipper (const RECT *cliprc, int *_x0, int *_y0, int *_x1, int *_y1)
	The line clipper using Cohen-Sutherland algorithm. More...
MG_EXPORT void GUIAPI	LineGenerator (void *context, int x1, int y1, int x2, int y2, CB_LINE cb)
	A line generator based-on Breshenham algorithm. More...
MG_EXPORT void GUIAPI	CircleGenerator (void *context, int sx, int sy, int r, CB_CIRCLE cb)
	A circle generator. More...
MG_EXPORT void GUIAPI	EllipseGenerator (void *context, int sx, int sy, int rx, int ry, CB_ELLIPSE cb)
	An ellipse generator. More...
MG_EXPORT void GUIAPI	CircleArcGenerator (void *context, int sx, int sy, int r, int ang1, int ang2, CB_ARC cb)
	An arc generator. More...
MG_EXPORT BOOL GUIAPI	MonotoneVerticalPolygonGenerator (void *context, const POINT *pts, int vertices, CB_POLYGON cb)
	A monotone vertical polygon generator. More...
MG_EXPORT BOOL GUIAPI	PolygonIsMonotoneVertical (const POINT *pts, int vertices)
	Checks a polygon is monotone vertical or not. More...
MG_EXPORT BOOL GUIAPI	PolygonGeneratorEx (void *context, const POINT *pts, int vertices, CB_POLYGON cb, RECT *rc_output)
	A general polygon generator. More...
MG_EXPORT BOOL GUIAPI	FloodFillGenerator (void *context, const RECT *src_rc, int x, int y, CB_EQUAL_PIXEL cb_equal_pixel, CB_FLOOD_FILL cb_flood_fill)
	A flood filling generator. More...
MG_EXPORT int GUIAPI	SetBitmapScalerType (HDC hdc, int scaler_type)
	set bitmap scaler algorithm callback of DC according by scaler_type. More...
MG_EXPORT void GUIAPI	MoveTo (HDC hdc, int x, int y)
	Moves the current zero pen position. More...
MG_EXPORT void GUIAPI	LineTo (HDC hdc, int x, int y)
	Draws a zero line to a position. More...
MG_EXPORT void GUIAPI	Rectangle (HDC hdc, int x0, int y0, int x1, int y1)
	Draws a rectangle. More...
MG_EXPORT void GUIAPI	PolyLineTo (HDC hdc, const POINT *pts, int vertices)
	Draws a polyline. More...
MG_EXPORT void GUIAPI	SplineTo (HDC hdc, const POINT *pts)
	Draws a bezier spline. More...
MG_EXPORT void GUIAPI	Circle (HDC hdc, int sx, int sy, int r)
	Draws a circle. More...
MG_EXPORT void GUIAPI	Ellipse (HDC hdc, int sx, int sy, int rx, int ry)
	Draws a ellipse. More...
MG_EXPORT void GUIAPI	CircleArc (HDC hdc, int sx, int sy, int r, int ang1, int ang2)
	Draws an arc. More...
MG_EXPORT void GUIAPI	FillBox (HDC hdc, int x, int y, int w, int h)
	Fills a rectangle box. More...
MG_EXPORT void GUIAPI	FillCircle (HDC hdc, int sx, int sy, int r)
	Fills a circle. More...
MG_EXPORT void GUIAPI	FillEllipse (HDC hdc, int sx, int sy, int rx, int ry)
	Fills an ellipse. More...
MG_EXPORT BOOL GUIAPI	FillPolygon (HDC hdc, const POINT *pts, int vertices)
	Fills an polygon. More...
MG_EXPORT BOOL GUIAPI	FloodFill (HDC hdc, int x, int y)
	Fills an enclosed area starting at point (x,y). More...

Detailed Description

Macro Definition Documentation

#define DrawHDotLine	(		hdc,
			x,
			y,
			w
	)		DrawHVDotLine (hdc, x, y, w, TRUE);

Draws a horizontal dot dash line.

This function draws a horizontal dot dash line with the zero pen.

Parameters

hdc	The device context.
x	x,y: The start point of the line.
y	x,y: The start point of the line.
w	The width of the horizontal dot line.

Note

Defined as a macro calling DrawHVDotLine.

See also

DrawVDotLine, DrawHVDotLine

Definition at line 2947 of file gdi.h.

#define DrawVDotLine	(		hdc,
			x,
			y,
			h
	)		DrawHVDotLine (hdc, x, y, h, FALSE);

Draws a vertical dot line.

This function draws a vertical dot dash line with the zero pen.

Parameters

hdc	The device context.
x	x,y: The start point of the line.
y	x,y: The start point of the line.
h	The height of the horizontal dot line.

Note

Defined as a macro calling DrawHVDotLine.

See also

DrawHDotLine, DrawHVDotLine

Definition at line 2965 of file gdi.h.

#define PolygonGenerator	(		context,
			pts,
			vertices,
			cb
	)		PolygonGeneratorEx(context, pts, vertices, cb, NULL)

This is a general polygon generator.

Defined as a macro calling PolygonGeneratorEx passing and rc_output as NULL.

See also

PolygonGeneratorEx

Definition at line 3235 of file gdi.h.

Typedef Documentation

typedef void(* CB_ARC)(void *context, int x, int y)

The type of arc generator callback.

Definition at line 3103 of file gdi.h.

typedef void(* CB_CIRCLE)(void *context, int x1, int x2, int y)

The type of circle generator callback.

Definition at line 3034 of file gdi.h.

typedef void(* CB_ELLIPSE)(void *context, int x1, int x2, int y)

The type of ellipse generator callback.

Definition at line 3070 of file gdi.h.

typedef BOOL(* CB_EQUAL_PIXEL)(void *context, int x, int y)

Flodd filling generator's equation callback.

Definition at line 3242 of file gdi.h.

typedef void(* CB_FLOOD_FILL)(void *context, int x1, int x2, int y)

Flodd filling generator's scan line callback.

Definition at line 3248 of file gdi.h.

typedef void(* CB_LINE)(void *context, int stepx, int stepy)

The type of line generator callback.

Definition at line 3003 of file gdi.h.

typedef void(* CB_POLYGON)(void *context, int x1, int x2, int y)

The type of polygon generator callback.

Definition at line 3135 of file gdi.h.

Function Documentation

void GUIAPI Circle	(	HDC	hdc,
		int	sx,
		int	sy,
		int	r
	)

Draws a circle.

This function draws a circle with the zero pen on the DC hdc. The center of the circle is at (sx, sy), and the radius is r.

Parameters

hdc	The device context.
sx	sx,sy: The center of the circle.
sy	sx,sy: The center of the circle.
r	The radius of the circle.

See also

CircleGenerator

void GUIAPI CircleArc	(	HDC	hdc,
		int	sx,
		int	sy,
		int	r,
		int	ang1,
		int	ang2
	)

Draws an arc.

This function draws an arc with the zero pen on the DC hdc. The center of the arc is at (sx, sy), the radius is r, and the radians of start angle and end angle are ang1 and ang2 respectively.

Parameters

hdc	The device context.
sx	sx,sy: The center of the arc.
sy	sx,sy: The center of the arc.
r	The radius of the arc.
ang1	The start angle of the arc, relative to the 3 o'clock position, counter-clockwise, in 1/64ths of a degree.
ang2	The end angle of the arc, relative to angle1, in 1/64ths of a degree.

See also

CircleArcGenerator, Fixed point math functions, DC attribute operations

void GUIAPI CircleArcGenerator	(	void *	context,
		int	sx,
		int	sy,
		int	r,
		int	ang1,
		int	ang2,
		CB_ARC	cb
	)

An arc generator.

This is a general arc generator. When it generates a point on the arc, it will call the callback cb and pass the context context, the coordinates of the point.

MiniGUI implements CircleArc function by using this generator.

Parameters

context	The context, will be passed to the callback cb.
sx	sx,sy: The center of the arc.
sy	sx,sy: The center of the arc.
r	The radius of the arc.
ang1	The start angle of the arc, relative to the 3 o'clock position, counter-clockwise, in 1/64ths of a degree.
ang2	The end angle of the arc, relative to angle1, in 1/64ths of a degree.
cb	The arc generator callback.

See also

CircleArc, CB_ARC

void GUIAPI CircleGenerator	(	void *	context,
		int	sx,
		int	sy,
		int	r,
		CB_CIRCLE	cb
	)

A circle generator.

This is a general circle generator, it will generate two points on the same horizontal scan line at every turn. When it generates the points on the circle, it will call the callback cb and pass the context context, the y-coordinate of the scan line, the x-coordinate of the left point on the scan line, and the x-coordinate of the right point. Note that in some cases, the left point and the right point will be the same.

MiniGUI implements Circle, FillCircle and InitCircleRegion functions by using this generator.

Parameters

context	The context, will be passed to the callback cb.
sx	sx,sy: The center of the circle.
sy	sx,sy: The center of the circle.
r	The radius of the circle.
cb	The circle generator callback.

See also

Circle, FillCircle, InitCircleRegion, CB_CIRCLE

Example:

/*
 * Draw a circle which is 4 pixels wide by using CircleGenerator.
 */
static void draw_circle_pixel (void* context, int x1, int x2, int y)
{
    HDC hdc = (HDC) context;

    FillCircle (hdc, x1, y, 2);
    FillCircle (hdc, x2, y, 2);
}

void DrawMyCircle (HDC hdc, int x, int y, int r, gal_pixel pixel)
{
    gal_pixel old_brush;

    old_bursh = SetBrushColor (hdc, pixle);

    CircleGenerator ((void*)hdc, x, y, r, draw_circle_pixel);
    
    SetBrushColor (hdc, old_brush);
}

void GUIAPI DrawHVDotLine	(	HDC	hdc,
		int	x,
		int	y,
		int	w_h,
		BOOL	H_V
	)

Draws a horizontal or vertical dot dash line.

This function draws a horizontal or vertical dot dash line with the zero pen.

Parameters

hdc	The device context.
x	x,y: The start point of the line.
y	x,y: The start point of the line.
w_h	The width of the line or horizontal dot line, or the height if you want to draw a vertical dot line.
H_V	Specify whether you want to draw a horizontal or vertical line. TRUE for horizontal, FALSE for vertical.

See also

FocusRect

Referenced by DWORD2Pixel().

gal_pixel DWORD2Pixel ( HDC  hdc, DWORD  dword  )

inlinestatic

An inline function to convert DWORD color to gal_pixel.

This function converts a color in DWORD to pixel value.

Parameters

hdc	The device context.
dword	The color value in DWORD.

Returns

The converted pixel value.

Definition at line 2886 of file gdi.h.

References DrawHVDotLine(), FocusRect(), GetAValue, GetBValue, GetGValue, GetRValue, and RGBA2Pixel().

void GUIAPI Ellipse	(	HDC	hdc,
		int	sx,
		int	sy,
		int	rx,
		int	ry
	)

Draws a ellipse.

This function draws an ellipse with the zero pen on the DC hdc. The center of the ellipse is at (sx, sy), the x-coordinate radius is rx, and the y-coordinate radius is ry.

Parameters

hdc	The device context.
sx	sx,sy: The center of the ellipse.
sy	sx,sy: The center of the ellipse.
rx	The x-coordinate radius of the ellipse.
ry	The y-coordinate radius of the ellipse.

See also

EllipseGenerator, DC attribute operations

void GUIAPI EllipseGenerator	(	void *	context,
		int	sx,
		int	sy,
		int	rx,
		int	ry,
		CB_ELLIPSE	cb
	)

An ellipse generator.

This is a general ellipse generator, it will generate two points on the same horizontal scan line at every turn. When it generates the points on the ellipse, it will call the callback cb and pass the context context, the y-coordinate of the scan line, the x-coordinate of the left point on the scan line, and the x-coordinate of the right point. Note that in some cases, the left point and the right point will be the same.

MiniGUI implements Ellipse, FillEllipse, and InitEllipseRegion functions by using this generator.

Parameters

context	The context, will be passed to the callback cb.
sx	sx,sy: The center of the ellipse.
sy	sx,sy: The center of the ellipse.
rx	The x-radius of the ellipse.
ry	The y-radius of the ellipse.
cb	The ellipse generator callback.

See also

Ellipse, FillEllipse, InitEllipseRegion, CB_CIRCLE

void GUIAPI FillBox	(	HDC	hdc,
		int	x,
		int	y,
		int	w,
		int	h
	)

Fills a rectangle box.

This function fills a box with the current brush in the DC hdc.

Parameters

hdc	The device context.
x	x,y: The coorinates of the upper-left corner of the box.
y	x,y: The coorinates of the upper-left corner of the box.
w	The width of the box.
h	The height of the box.

See also

DC attribute operations

void GUIAPI FillCircle	(	HDC	hdc,
		int	sx,
		int	sy,
		int	r
	)

Fills a circle.

This function fills a circle with the current brush in the DC hdc.

Parameters

hdc	The device context.
sx	sx,sy: The center of the circle.
sy	sx,sy: The center of the circle.
r	The radius of the circle.

See also

CircleGenerator, DC attribute operations

void GUIAPI FillEllipse	(	HDC	hdc,
		int	sx,
		int	sy,
		int	rx,
		int	ry
	)

Fills an ellipse.

This function fills an ellipse with the current brush in the DC hdc. Note that MiniGUI only defined the color property for the brush objects so far.

Parameters

hdc	The device context.
sx	sx,sy: The center of the circle.
sy	sx,sy: The center of the circle.
rx	The x-coordinate radius of the ellipse.
ry	The y-coordinate radius of the ellipse.

See also

EllipseGenerator, DC attribute operations

BOOL GUIAPI FillPolygon	(	HDC	hdc,
		const POINT *	pts,
		int	vertices
	)

Fills an polygon.

This function fills a polygon with the current brush in the DC hdc.

Parameters

hdc	The device context.
pts	The pointer to the vertex array of the polygon.
vertices	The number of the vertices, i.e. the size of the vertex array.

See also

PolygonGenerator, DC attribute operations

BOOL GUIAPI FloodFill	(	HDC	hdc,
		int	x,
		int	y
	)

Fills an enclosed area starting at point (x,y).

This function fills an enclosed area staring at point (x,y), and stops when encountering a pixel different from the start point.

Parameters

hdc	The device context.
x	x,y: The start point.
y	x,y: The start point.

See also

FloodFillGenerator, DC attribute operations

BOOL GUIAPI FloodFillGenerator	(	void *	context,
		const RECT *	src_rc,
		int	x,
		int	y,
		CB_EQUAL_PIXEL	cb_equal_pixel,
		CB_FLOOD_FILL	cb_flood_fill
	)

A flood filling generator.

This function is a general flood filling generator.

MiniGUI implements FloodFill function by using this generator.

Parameters

context	The context, will be passed to the callback cb.
src_rc	The filling bounding rectangle.
x	x,y: The start filling point.
y	x,y: The start filling point.
cb_equal_pixel	The callback to check the pixel is equal with the start point or not.
cb_flood_fill	The callback to fill a scan line.

See also

FloodFill, CB_EQUAL_PIXEL, CB_FLOOD_FILL

void GUIAPI FocusRect	(	HDC	hdc,
		int	x0,
		int	y0,
		int	x1,
		int	y1
	)

Draws a focus rectangle.

This function uses XOR mode to draw the focus rectangle on the device context, i.e. calling this function then calling this function with same arguments again will erase the focus rectangle and restore the pixels before the first call.

Parameters

hdc	The device context.
x0	x0,y0: The coordinates of upper-left corner of the rectangle.
y0	x0,y0: The coordinates of upper-left corner of the rectangle.
x1	x1,y1: The corrdinates of lower-right corner of the rectangle.
y1	x1,y1: The corrdinates of lower-right corner of the rectangle.

See also

DrawHVDotLine

Referenced by DWORD2Pixel().

gal_pixel GUIAPI GetPixel	(	HDC	hdc,
		int	x,
		int	y
	)

Gets the pixel value at the specified position on a DC.

This function gets the pixel value at the specified position (x,y) on the DC hdc.

Parameters

hdc	The device context.
x	x,y: The pixel position.
y	x,y: The pixel position.

Returns

The pixel value.

See also

SetPixel

gal_pixel GUIAPI GetPixelRGB	(	HDC	hdc,
		int	x,
		int	y,
		Uint8 *	r,
		Uint8 *	g,
		Uint8 *	b
	)

Gets the pixel value at the specified position on a DC in RGB triple.

This function gets the pixel value at the specified position (x,y) on the DC hdc in RGB triple.

Parameters

hdc	The device context.
x	x,y: The pixel position.
y	x,y: The pixel position.
r	The red component of the pixel will be returned through this pointer.
g	The green component of the pixel will be returned through this pointer.
b	The blue component of the pixel will be returned through this pointer.

Returns

The pixel value.

See also

SetPixelRGB

gal_pixel GUIAPI GetPixelRGBA	(	HDC	hdc,
		int	x,
		int	y,
		Uint8 *	r,
		Uint8 *	g,
		Uint8 *	b,
		Uint8 *	a
	)

Gets the pixel value at the specified position on a DC in RGBA quarter.

This function gets the pixel value at the specified position (x,y) on the DC hdc in RGBA quarter.

Parameters

hdc	The device context.
x	x,y: The pixel position.
y	x,y: The pixel position.
r	The red component of the pixel will be returned through this pointers.
g	The green component of the pixel will be returned through this pointers.
b	The blue component of the pixel will be returned through this pointers.
a	The alpha component of the pixel will be returned through this pointers.

Returns

The pixel value.

See also

SetPixelRGBA

BOOL GUIAPI LineClipper	(	const RECT *	cliprc,
		int *	_x0,
		int *	_y0,
		int *	_x1,
		int *	_y1
	)

The line clipper using Cohen-Sutherland algorithm.

This function clips a line from (*_x0,*_y0) to (*_x1, *_y1) with the specified clipping rectangle pointed to by cliprc. Then return the clipped line throught the pointers (_x0, _y0, _x1, _y1).

It is modified to do pixel-perfect clipping. This means that it will generate the same endpoints that would be drawn if an ordinary Bresenham line-drawer where used and only visible pixels drawn.

Parameters

cliprc	The Pointer to the clipping rectangle.
_x0	_x0,_y0: The pointers contains the start point of the line. The start point after clipping will be returned through them as well as.
_y0	_x0,_y0: The pointers contains the start point of the line. The start point after clipping will be returned through them as well as.
_x1	_x1,_y1: The pointers contains the end point of the line. The end point after clipping will be returned through them as well as.
_y1	_x1,_y1: The pointers contains the end point of the line. The end point after clipping will be returned through them as well as.

Returns

TRUE for clipped by the clipping rectangle, FALSE for not clipped.

See also

LineGenerator

void GUIAPI LineGenerator	(	void *	context,
		int	x1,
		int	y1,
		int	x2,
		int	y2,
		CB_LINE	cb
	)

A line generator based-on Breshenham algorithm.

This is a Breshenham line generator. When it generates a new point on the line, it will call the callback cb and pass the context context and the step values on x-coordinate and y-coodinate since the last point. The first generated point always be the start point you passed to this function. Thus, the first step values passed to cb will be (0,0).

MiniGUI implements LineTo function by using this generator.

Parameters

context	The context, will be passed to the callback cb.
x1	x1,y1: The start point of the line.
y1	x1,y1: The start point of the line.
x2	x2,y2: The end point of the line.
y2	x2,y2: The end point of the line.
cb	The line generator callback.

See also

LineTo, LineClipper, CB_LINE

void GUIAPI LineTo	(	HDC	hdc,
		int	x,
		int	y
	)

Draws a zero line to a position.

This function draws a line from the current zero pen position to (x,y), and then moves the zero pen position to (x,y) by using the zero pen. The next zero line drawing operation will start from the position.

Parameters

hdc	The device context.
x	x,y: The end point of the line.
y	x,y: The end point of the line.

See also

MoveTo, LineGenerator, DC attribute operations

BOOL GUIAPI MonotoneVerticalPolygonGenerator	(	void *	context,
		const POINT *	pts,
		int	vertices,
		CB_POLYGON	cb
	)

A monotone vertical polygon generator.

This is a monotone vertical polygon generator.

"Monoton vertical" means "monotone with respect to a vertical line"; that is, every horizontal line drawn through the polygon at any point would cross exactly two active edges (neither horizontal lines nor zero-length edges count as active edges; both are acceptable anywhere in the polygon). Right & left edges may cross (polygons may be nonsimple). Polygons that are not convex according to this definition won't be drawn properly.

You can call PolygonIsMonotoneVertical function to check one polygon is monotone vertical or not.

This function will generate two points on the same horizontal scan line at every turn. When it generates the points on the polygon, it will call the callback cb and pass the context context, the y-coordinate of the scan line, the x-coordinate of the left point on the scan line, and the x-coordinate of the right point. Note that in some cases, the left point and the right point will be the same.

MiniGUI implements FillPolygon and InitPolygonRegion functions by using this generator.

Parameters

context	The context, will be passed to the callback cb.
pts	The pointer to the vertex array of the polygon.
vertices	The number of the vertices, i.e. the size of the vertex array.
cb	The polygon generator callback.

Returns

TRUE on success, FALSE on error.

See also

FillPolygon, InitPolygonRegion, PolygonIsMonotoneVertical, CB_CIRCLE

void GUIAPI MoveTo	(	HDC	hdc,
		int	x,
		int	y
	)

Moves the current zero pen position.

This function moves the current pen position of the DC hdc to (x,y). The next line or other pen drawing operation will start from the position.

Parameters

hdc	The device context.
x	x,y: The new pen position.
y	x,y: The new pen position.

See also

LineTo

DWORD GUIAPI Pixel2DWORD ( HDC  hdc, gal_pixel  pixel  )

inlinestatic

An inline function to convert pixel value to DWORD color.

This function converts a pixel value to color in DWORD.

Parameters

hdc	The device context.
pixel	The pixel value to be converted.

Returns

The converted color value in DWORD.

Definition at line 2867 of file gdi.h.

References MakeRGBA, and Pixel2RGBA().

void GUIAPI Pixel2RGB ( HDC  hdc, gal_pixel  pixel, Uint8 *  r, Uint8 *  g, Uint8 *  b  )

inlinestatic

Gets the color in RGB triple from a pixel value under a DC.

This function gets the color in RGB triple from the pixel value pixel under the DC hdc.

Parameters

hdc	The device context.
pixel	The pixel value.
r	The red component of the pixel will be returned through this pointer.
g	The green component of the pixel will be returned through this pointer.
b	The blue component of the pixel will be returned through this pointer.

Note

This function is implemented as an inline to RGB2Pixels.

See also

Pixel2RGBs, RGB2Pixel

Definition at line 2801 of file gdi.h.

References _RGB::b, _RGB::g, Pixel2RGBAs(), Pixel2RGBs(), and _RGB::r.

void GUIAPI Pixel2RGBA ( HDC  hdc, gal_pixel  pixel, Uint8 *  r, Uint8 *  g, Uint8 *  b, Uint8 *  a  )

inlinestatic

Gets the color in RGBA quarter from a pixel value under a DC.

This function gets the color in RGBA quarter from the pixel value pixel under the DC hdc.

Parameters

hdc	The device context.
pixel	The pixel value.
r	The red component of the pixel will be returned through this pointer.
g	The green component of the pixel will be returned through this pointer.
b	The blue component of the pixel will be returned through this pointer.
a	The alpha component of the pixel will be returned through this pointer.

Note

This function is implemented as an inline to RGBA2Pixels.

See also

RGBA2Pixels, RGB2Pixel

Definition at line 2849 of file gdi.h.

References _RGB::a, _RGB::b, _RGB::g, Pixel2RGBAs(), and _RGB::r.

Referenced by Pixel2DWORD().

void GUIAPI Pixel2RGBAs	(	HDC	hdc,
		const gal_pixel *	pixels,
		RGB *	rgbs,
		int	count
	)

Gets the colors in RGBA quarter from a array of pixel values under a DC.

This function gets the colors in RGBA quarter from the pixel value array pixels under the DC hdc.

Parameters

hdc	The device context.
pixels	The array of pixel values.
rgbs	The array returns the converted RGB quarters.
count	The number of pixels.

See also

RGB2Pixels

Referenced by Pixel2RGB(), and Pixel2RGBA().

void GUIAPI Pixel2RGBs	(	HDC	hdc,
		const gal_pixel *	pixels,
		RGB *	rgbs,
		int	count
	)

Gets the colors in RGB triple from a pixel value array under a DC.

This function gets the colors in RGB triple from the pixel value array pixels under the DC hdc.

Parameters

hdc	The device context.
pixels	The array of pixel values.
rgbs	The array returns the converted RGB triples.
count	The number of pixels.

See also

RGB2Pixels

Referenced by Pixel2RGB(), and RGB2Pixel().

BOOL GUIAPI PolygonGeneratorEx	(	void *	context,
		const POINT *	pts,
		int	vertices,
		CB_POLYGON	cb,
		RECT *	rc_output
	)

A general polygon generator.

This is a general polygon generator.

This function will generate two points on the same horizontal scan line at every turn. When it generates the points on the polygon, it will call the callback cb and pass the context context, the y-coordinate of the scan line, the x-coordinate of the left point on the scan line, and the x-coordinate of the right point. Note that in some cases, the left point and the right point will be the same.

MiniGUI implements FillPolygon and InitPolygonRegion functions by using this generator.

Parameters

context	The context, will be passed to the callback cb.
pts	The pointer to the vertex array of the polygon.
vertices	The number of the vertices, i.e. the size of the vertex array.
cb	The polygon generator callback.
rc_output	The limit RECT for Polygon ScanLines ranges .

See also

FillPolygon, InitPolygonRegion, CB_CIRCLE

BOOL GUIAPI PolygonIsMonotoneVertical	(	const POINT *	pts,
		int	vertices
	)

Checks a polygon is monotone vertical or not.

This function checks if the given polygon is monotone vertical.

Parameters

pts	The pointer to the vertex array of the polygon.
vertices	The number of the vertices, i.e. the size of the vertex array.

Returns

TRUE if it is monotonoe vertical, otherwise FALSE.

Note

To make sure a polygon is monotone vertical, the polygon must be a closed one, that is, the pts[0] must be equal to the pts[vertices-1].

See also

MonotoneVerticalPolygonGenerator

void GUIAPI PolyLineTo	(	HDC	hdc,
		const POINT *	pts,
		int	vertices
	)

Draws a polyline.

This function draws a polyline by using MoveTo and LineTo. The current zero pen position after calling this function will be the last vertex of the polyline.

Parameters

hdc	The device context.
pts	The pointer to the vertex array of the polyline.
vertices	The number of the vertices.

See also

MoveTo, LineTo

void GUIAPI Rectangle	(	HDC	hdc,
		int	x0,
		int	y0,
		int	x1,
		int	y1
	)

Draws a rectangle.

This function draws a rectangle by using MoveTo and LineTo. The current zero pen position after calling this function will be (x1,y1).

Parameters

hdc	The device context.
x0	x0,y0: The coordinates of the upper-left corner of the rectangle.
y0	x0,y0: The coordinates of the upper-left corner of the rectangle.
x1	x1,y1: The coordinates of the lower-right corner of the rectangle.
y1	x1,y1: The coordinates of the lower-right corner of the rectangle.

See also

MoveTo, LineTo

gal_pixel GUIAPI RGB2Pixel ( HDC  hdc, Uint8  r, Uint8  g, Uint8  b  )

inlinestatic

Gets the pixel value from a color in RGB triple under a DC.

This function gets the pixel value from the RGB triple (r,g,b) under the DC hdc.

Parameters

hdc	The device context.
r	The red component of a color.
g	The green component of a color.
b	The blue component of a color.

Returns

The pixel value.

Note

This function is implemented as an inline to RGB2Pixels.

See also

RGB2Pixels, Pixel2RGB

Definition at line 2754 of file gdi.h.

References Pixel2RGBs(), and RGB2Pixels().

void GUIAPI RGB2Pixels	(	HDC	hdc,
		const RGB *	rgbs,
		gal_pixel *	pixels,
		int	count
	)

Gets the pixel values from a color array in RGB triple under a DC.

This function gets the pixel values from the RGB triple array rgbs under the DC hdc.

Parameters

hdc	The device context.
rgbs	The array of RGB triples to be converted.
pixels	The array returns the converted pixel values.
count	The number of RGB triples.

See also

Pixel2RGBs

Referenced by RGB2Pixel(), and RGBA2Pixel().

gal_pixel GUIAPI RGBA2Pixel ( HDC  hdc, Uint8  r, Uint8  g, Uint8  b, Uint8  a  )

inlinestatic

Gets the pixel value from a color in RGBA quarter under a DC.

This function gets the pixel value from the RGB quarter (r,g,b,a) under the DC hdc.

Parameters

hdc	The device context.
r	The red component of a color.
g	The green component of a color.
b	The blue component of a color.
a	The alpha component of a color.

Returns

The pixel value.

Note

This function is implemented as an inline to RGBA2Pixels.

See also

RGBA2Pixels, Pixel2RGBA

Definition at line 2710 of file gdi.h.

References RGB2Pixels(), and RGBA2Pixels().

Referenced by DWORD2Pixel().

void GUIAPI RGBA2Pixels	(	HDC	hdc,
		const RGB *	rgbs,
		gal_pixel *	pixels,
		int	count
	)

Gets the pixel values from a color array in RGBA quarter under a DC.

This function gets the pixel values from the RGB quarter array rgbs under the DC hdc.

Parameters

hdc	The device context.
rgbs	The array of RGBA quarters to be converted.
pixels	The array returns the converted pixel values.
count	The number of RGBA quarters.

See also

Pixel2RGBAs

Referenced by RGBA2Pixel().

int GUIAPI SetBitmapScalerType	(	HDC	hdc,
		int	scaler_type
	)

set bitmap scaler algorithm callback of DC according by scaler_type.

This function is a set general bitmap scaler type that is DDA or Bilinear interpolation algorithm. MiniGUI implements StretchBlt functions by using this scaler.

Parameters

hdc	The device context.
scaler_type	The type of scaler algorithm, BITMAP_SCALER_DDA or BITMAP_SCALER_BILINEAR.

See also

BitmapDDAScaler, BitmapBinearScaler

void GUIAPI SetPixel	(	HDC	hdc,
		int	x,
		int	y,
		gal_pixel	pixel
	)

Sets the pixel with a new pixel value at the specified position on a DC.

This function sets the pixel with a pixel value pixel at the specified position (x,y) on the DC hdc. You can the pre-defined standard system pixel values.

Parameters

hdc	The device context.
x	x,y: The pixel position.
y	x,y: The pixel position.
pixel	The pixel value.

See also

GetPixel, System colors and pixel values.

gal_pixel GUIAPI SetPixelRGB	(	HDC	hdc,
		int	x,
		int	y,
		Uint8	r,
		Uint8	g,
		Uint8	b
	)

Sets the pixel by a RGB triple at the specified position on a DC.

This function sets the pixel with a RGB triple (r,g,b) at the specified position (x,y) on the DC hdc.

Parameters

hdc	The device context.
x	x,y: The pixel position.
y	x,y: The pixel position.
r	The red component of a color.
g	The green component of a color.
b	The blue component of a color.

Returns

The pixel value of the RGB triple.

See also

GetPixel, RGB2Pixel

gal_pixel GUIAPI SetPixelRGBA	(	HDC	hdc,
		int	x,
		int	y,
		Uint8	r,
		Uint8	g,
		Uint8	b,
		Uint8	a
	)

Sets the pixel by a RGBA quarter at the specified position on a DC.

This function sets the pixel with a RGBA quarter (r,g,b,a) at the specified position (x,y) on the DC hdc.

Parameters

hdc	The device context.
x	x,y: The pixel position.
y	x,y: The pixel position.
r	The red component of a color.
g	The green component of a color.
b	The blue component of a color.
a	The alpha component of a color.

Returns

The pixel value of the RGBA quarter.

See also

GetPixel, RGBA2Pixel

void GUIAPI SplineTo	(	HDC	hdc,
		const POINT *	pts
	)

Draws a bezier spline.

This function draws a bezier spline by using MoveTo and LineTo. The current pen position after calling this function will be the last control point of the spline. Note that the number of the control points should always be 4.

Parameters

hdc	The device context.
pts	The pointer to the control point array of the spline.

See also

MoveTo, LineTo