path: root/xc/test/xsuite/xtest/tset/CH06/drwarc/drwarc.m

/*
 * Copyright 1990, 1991 by the Massachusetts Institute of Technology and
 * UniSoft Group Limited.
 * 
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and that
 * both that copyright notice and this permission notice appear in
 * supporting documentation, and that the names of MIT and UniSoft not be
 * used in advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.  MIT and UniSoft
 * make no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 * $XConsortium$
 */
>>TITLE XDrawArc CH06
void

Display	*display = Dsp;
Drawable d;
GC		gc;
int 	x = 10;
int 	y = 10;
unsigned int 	width = 60;
unsigned int 	height = 60;
int 	angle1 = DEG(270);
int 	angle2 = DEG(321);
>>EXTERN
#define DEG(n)  (n*64)  /* Convert from degrees to units used by call */

/*
 * This will draw a straight line for horizontal and vertical lines
 * for other lines, draw a hor line using the horizontal extent.
 */
static void
drawline(ax1, ay1, ax2, ay2)
int	 ax1, ay1, ax2, ay2;
{
int 	negw = 0;
int 	negh = 0;
int 	pass = 0, fail = 0;

	x = ax1; y = ay1;

	if (ax2 > ax1) {
		width = ax2-ax1;
	} else {
		width = ax1-ax2;
		x -= width;
		negw = 1;
	}
	if (ay2 > ay1) {
		height = ay2-ay1;
	} else {
		height = ay1-ay2;
		y -= height;
		negh = 1;
	}

	if (width == 0) {
		/* Vertical line */
		if (negh) {
			angle1 = DEG(270);
			angle2 = DEG(180);
		} else {
			angle1 = DEG(90);
			angle2 = DEG(180);
		}
	} else if (height == 0) {
		/* Horizontal line */
		if (negw) {
			angle1 = DEG(0);
			angle2 = DEG(180);
		} else {
			angle1 = DEG(180);
			angle2 = DEG(180);
		}
	} else {
		/* Horizontal line */
		if (negw) {
			angle1 = DEG(0);
			angle2 = DEG(180);
		} else {
			angle1 = DEG(180);
			angle2 = DEG(180);
		}
		height = 0;
	}

	XCALL;
}

static void
setfordash()
{
	x = 20; y = 20;
	width = 49; height = 0;
	angle1 = DEG(180);
	angle2 = DEG(180);
}
>>ASSERTION Good A
A call to xname draws a single circular or elliptical arc in the drawable
.A d
as specified by
.A x ,
.A y ,
.A width ,
.A height ,
.A angle1
and
.A angle2 .
>>STRATEGY
Draw simple arc.
Pixmap verify.
>>CODE
XVisualInfo	*vp;

	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		XCALL;

		PIXCHECK(display, d);
	}

	CHECKPASS(nvinf());
>>ASSERTION def
The centre of the circle or ellipse is the centre of the specified rectangle,
with top left corner at
.A x
and
.A y
and the major and minor axes are specified by the rectangle's
.A width
and
.A height .
>>ASSERTION def COM
The start of the arc is specified by the
.A angle1
argument, in units of degrees * 64, relative to the three -o'clock
position from the centre.
>>ASSERTION def COM
The path and extent of the arc relative to the
start of the arc is specified by the
.A angle2
argument, in units of degrees * 64.
>>ASSERTION Good A
When the angles are positive,
then a call to xname draws the arc in the counterclockwise direction.
>>STRATEGY
Draw arc with positive angle2.
Pixmap verify.
>>CODE
XVisualInfo	*vp;

	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		angle2 = DEG(30);
		XCALL;

		PIXCHECK(display, d);
	}

	CHECKPASS(nvinf());
>>ASSERTION Good A
When the angles are negative,
then a call to xname draws the arc in the clockwise direction.
>>STRATEGY
Draw arc with negative angle2.
Pixmap verify.
>>CODE
XVisualInfo	*vp;

	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		angle2 = DEG(-30);
		XCALL;

		PIXCHECK(display, d);
	}

	CHECKPASS(nvinf());
>>ASSERTION Good A
When the magnitude of angle2 is greater than 360 degrees, 
then it is truncated to 360 degrees.
>>STRATEGY
Set function to GXxor.
Draw arc with angle2 equal to 400 degrees.
Check result is same as angle2 equal to 360 degrees.
>>CODE
XVisualInfo	*vp;
XImage	*sav;

	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		angle2 = DEG(360);
		XCALL;
		sav = savimage(display, d);
		dclear(display, d);

		XSetFunction(display, gc, GXxor);
		angle2 = DEG(400);
		XCALL;

		if (compsavimage(display, d, sav))
			CHECK;
		else {
			report("angle2 was not truncated to 360");
			FAIL;
		}

	}

	CHECKPASS(nvinf());
>>ASSERTION def COM
An arc specified as %[ ~x, ~y, ~width , ~height, ~angle1, ~angle2 ]%, 
has the origin of the major and minor axes at 
% [ x +^ {width over 2} , ~y +^ {height over 2} ]%, 
the infinitely thin path describing the entire circle or ellipse 
intersects the horizontal axis at % [ x, ~y +^ {height over 2} ]% and 
% [ x +^ width , ~y +^ { height over 2 }] %
and the path intersects the vertical axis
at % [ x +^ { width over 2 } , ~y ]% and 
% [ x +^ { width over 2 }, ~y +^ height ]%.
>>ASSERTION def COM
When a wide line with line-width lw is used in a call to xname,
then the bounding outlines for filling are given
by the two infinitely thin paths consisting of all points whose perpendicular
distance from the path of the circle/ellipse is equal to lw/2.
>># NOTE		kieron	Arc definition will change soon, so defer.
>>ASSERTION def COM
The
.M cap_style
>>#and
>>#.M join_style
is applied the same as for a line corresponding to the tangent of the
circle/ellipse at the endpoint.
>>ASSERTION def COM
On a call to xname the angles are interpreted
in the effectively skewed coordinate system of the ellipse.
>>ASSERTION Good A
A call to xname does not draw a pixel more than once.
>>STRATEGY
Set gc function to GXcopy.
Call XDrawArc.
Set gc function to GXxor.
Call XDrawArc.
Verify that the result is the same in both cases.
>>CODE
XVisualInfo *vp;
XImage	*sav;

	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		XCALL;
		sav = savimage(display, d);
		dclear(display, d);

		XSetFunction(display, gc, GXxor);
		XCALL;
		if (compsavimage(display, d, sav))
			CHECK;
		else {
			report("A Pixel was drawn more than once");
			FAIL;
		}
	}
	CHECKPASS(nvinf());

>>ASSERTION Good A
When an arc is drawn with one endpoint and a clockwise extent
and another with the other endpoint and an equivalent counterclockwise extent,
then a call to xname draws the same pixels in each case.
>>STRATEGY
Draw arc and save result.
Draw arc in oposite direction.
Verify that result is the same.
>>CODE
XVisualInfo	*vp;
XImage	*sav;
int 	savang1;
int 	savang2;

	savang1 = angle1;
	savang2 = angle2;
	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		angle1 = savang1;
		angle2 = savang2;

		XCALL;
		sav = savimage(display, d);
		dclear(display, d);

		/* Reverse direction */
		angle1 += angle2;
		if (angle1 > DEG(360))
			angle1 -= DEG(360);
		angle2 = -angle2;

		XCALL;

		if (compsavimage(display, d, sav))
			CHECK;
		else {
			report("Drawing same arc backwards did not draw same pixels");
			FAIL;
		}
	}

	CHECKPASS(nvinf());
>>ASSERTION Good A
When either axis is zero, then a call to xname draws a horizontal or vertical
line.
>>STRATEGY
Draw arc with width zero.
Verify directly that the pixels drawn form a vertical line.
Draw arc with height zero.
Verify directly that the pixels drawn form a horizontal line.
>>CODE
XVisualInfo	*vp;
struct	area	area;

	for (resetvinf(VI_WIN_PIX); nextvinf(&vp); ) {
		d = makewin(display, vp);
		gc = makegc(display, d);

		width = 0;
		height = 30;
		setarea(&area, x, y, 1, height);
		XCALL;

		if (checkarea(display, d, &area, W_FG, W_BG, CHECK_ALL))
			CHECK;
		else {
			report("A straight line was not drawn when the arc had width 0");
			FAIL;
		}

		width = 30;
		height = 0;
		setarea(&area, x, y, width, 1);
		dclear(display, d);
		XCALL;

		if (checkarea(display, d, &area, W_FG, W_BG, CHECK_ALL))
			CHECK;
		else {
			report("A straight line was not drawn when the arc had height 0");
			FAIL;
		}
	}

	CHECKPASS(2*nvinf());
>>ASSERTION def COM
Angles are computed based solely on the coordinate system and ignore the
aspect ratio.
>>ASSERTION gc
On a call to xname the GC components
.M function ,
.M plane-mask ,
.M line-width ,
.M line-style ,
.M cap-style ,
>># This can not be right?
>># .M join-style ,
.M fill-style ,
.M subwindow-mode ,
.M clip-x-origin ,
.M clip-y-origin
and
.M clip-mask
are used.
>>ASSERTION gc
On a call to xname the GC mode-dependent components
.M foreground ,
.M background ,
.M tile ,
.M stipple ,
.M tile-stipple-x-origin ,
.M tile-stipple-y-origin ,
.M dash-offset 
and
.M dash-list
are used.
>>ASSERTION Bad A
.ER BadDrawable
>>ASSERTION Bad A
.ER BadGC
>>ASSERTION Bad A
.ER BadMatch inputonly
>>ASSERTION Bad A
.ER BadMatch gc-drawable-depth
>>ASSERTION Bad A
.ER BadMatch gc-drawable-screen
>># HISTORY steve Completed	Written in new format and style
>># HISTORY kieron Completed	Global and pixel checking to do - 19/11/90
>># HISTORY dave Completed	Final checking to do - 21/11/90
>># HISTORY steve Removed references to join-style.