Volume 7A: XView Programming Manual

Example F-5. The fonts.c program (continued)

void

change_font(item, value, event)

Panel_item item;

Event *event;

{

static int family, style, scale;

char buf[128];

Frame frame;

char *family_name;

char *style_name;

int scale_value;

Xv_Font font;

frame = (Frame)xv_get(xv_get(item, PANEL_PARENT_PANEL), XV_OWNER);

family_name = (char *)xv_get(family_item, PANEL_CHOICE_STRING,

xv_get(family_item, PANEL_VALUE));

style_name = (char *)xv_get(style_item, PANEL_CHOICE_STRING,

xv_get(style_item, PANEL_VALUE));

scale_value = (int) xv_get(scale_item, PANEL_VALUE);

xv_set(frame, FRAME_BUSY, TRUE, NULL);

font = (Xv_Font)xv_find(frame, FONT,

FONT_FAMILY, family_name,

FONT_STYLE, style_name,

/* scale_value happens to coincide with Window_rescale_state */

FONT_SCALE, scale_value,

/*

* If run on a server that cannot rescale fonts, only font

* sizes that exist should be passed

*/

FONT_SIZES_FOR_SCALE, 12, 14, 16, 22,

NULL);

xv_set(frame, FRAME_BUSY, FALSE, NULL);

if (!font) {

if (item == family_item) {

sprintf(buf, "cannot load ’%s’", family_name);

xv_set(family_item, PANEL_VALUE, family, NULL);

} else if (item == style_item) {

sprintf(buf, "cannot load ’%s’", style_name);

xv_set(style_item, PANEL_VALUE, style, NULL);

} else {

sprintf(buf, "Not available in %s scale.",

xv_get(scale_item, PANEL_CHOICE_STRING, scale));

xv_set(scale_item, PANEL_VALUE, scale, NULL);

}

xv_set(frame, FRAME_RIGHT_FOOTER, buf, NULL);

return;

}

if (item == family_item)

family = value;

else if (item == style_item)

style = value;

else

scale = value;

cur_font = (XFontStruct *)xv_get(font, FONT_INFO);

XSetFont(dpy, gc, cur_font->fid);

Example Programs

Example Programs 733

Example F-5. The fonts.c program (continued)

sprintf(buf, "Current font: %s", xv_get(font, FONT_NAME));

xv_set(frame, FRAME_LEFT_FOOTER, buf, NULL);

}

change_font_by_name(item, event)

Panel_item item;

Event *event;

{

char buf[128];

char *name = (char *)xv_get(item, PANEL_VALUE);

Frame frame = (Frame)xv_get(xv_get(item, XV_OWNER), XV_OWNER);

Xv_Font font;

xv_set(frame, FRAME_BUSY, TRUE, NULL);

font = (Xv_Font)font = (Xv_Font)xv_find(frame, FONT,

FONT_NAME, name,

NULL);

xv_set(frame, FRAME_BUSY, FALSE, NULL);

if (!font) {

sprintf(buf, "cannot load ’%s’", name);

xv_set(frame, FRAME_RIGHT_FOOTER, buf, NULL);

return PANEL_NONE;

}

cur_font = (XFontStruct *)xv_get(font, FONT_INFO);

XSetFont(dpy, gc, cur_font->fid);

sprintf(buf, "Current font: %s", xv_get(font, FONT_NAME));

xv_set(frame, FRAME_LEFT_FOOTER, buf, NULL);

return PANEL_NONE;

}

F.6 x_draw.c

This program uses several Xlib drawing functions to draw various types of geometric objects.

We integrate the XView color model (see Chapter 21, Color) to render each object in a dif-

ferent color.

Example F-6. The x_draw.c program

/*

* x_draw.c -- demonstrates the use of Xlib drawing functions

* inside an XView canvas. Color is used, but not required.

*/

#include <xview/xview.h>

#include <xview/canvas.h>

#include <xview/cms.h>

#include <xview/xv_xrect.h>

/* indices into color table renders specified colors. */

#define WHITE 0

#define RED 1

#define GREEN 2

734 XView Programming Manual

Example F-6. The x_draw.c program (continued)

#define BLUE 3

#define ORANGE 4

#define AQUA 5

#define PINK 6

#define BLACK 7

GC gc; /* GC used for Xlib drawing */

unsigned long *colors; /* the color table */

/*

* initialize cms data to support colors specified above. Assign

* data to new cms -- use either static or dynamic cms depending

* on -dynamic command line switch.

*/

main(argc, argv)

int argc;

char *argv[ ];

{

static char stipple_bits[ ] = {0xAA, 0xAA, 0x55, 0x55};

static Xv_singlecolor cms_colors[ ] = {

{ 255, 255, 255 },

{ 255, 0, 0 },

{ 0, 255, 0 },

{ 0, 0, 255 },

{ 250, 130, 80 },

{ 30, 230, 250 },

{ 230, 30, 250 },

};

Cms cms;

Frame frame;

Canvas canvas;

XFontStruct *font;

Display *display;

XGCValues gc_val;

XID xid;

void canvas_repaint();

Xv_cmsdata cms_data;

int use_dynamic = FALSE;

/* Create windows */

xv_init(XV_INIT_ARGC_PTR_ARGV, &argc, argv, NULL);

if (*++argv && !strcmp(*argv, "-dynamic"))

use_dynamic = TRUE;

frame = xv_create(NULL,FRAME,

FRAME_LABEL, "xv_canvas_x_draw",

XV_WIDTH, 400,

XV_HEIGHT, 300,

NULL);

cms = xv_create(NULL, CMS,

CMS_SIZE, 7,

CMS_TYPE, use_dynamic? XV_DYNAMIC_CMS : XV_STATIC_CMS,

CMS_COLORS, cms_colors,

NULL);

Example Programs

Example Programs 735

Example F-6. The x_draw.c program (continued)

canvas = xv_create(frame, CANVAS,

CANVAS_REPAINT_PROC, canvas_repaint,

CANVAS_X_PAINT_WINDOW, TRUE,

/* WIN_DYNAMIC_VISUAL, use_dynamic, */

XV_VISUAL_CLASS, PseudoColor,

WIN_CMS, cms,

NULL);

/* Get display and xid */

display = (Display *)xv_get(frame, XV_DISPLAY);

xid = (XID)xv_get(canvas_paint_window(canvas), XV_XID);

if (!(font = XLoadQueryFont(display, "fixed"))) {

puts("cannot load fixed font");

exit(1);

}

/* Create and initialize GC */

gc_val.font = font->fid;

gc_val.stipple =

XCreateBitmapFromData(display, xid, stipple_bits, 16, 2);

gc = XCreateGC(display, xid, GCFont | GCStipple, &gc_val);

/* get the colormap from the canvas now that

* the cms has been installed

*/

colors = (unsigned long *)xv_get(canvas, WIN_X_COLOR_INDICES);

/* Start event loop */

xv_main_loop(frame);

}

/*

* Draws onto the canvas using Xlib drawing functions.

*/

void

canvas_repaint(canvas, pw, display, xid, xrects)

Canvas canvas;

Xv_Window pw;

Display *display;

Window xid;

Xv_xrectlist *xrects;

{

static XPoint box[ ] = {

{0,0}, {100,100}, {0,-100}, {-100,100}, {0,-100}

};

static XPoint points[ ] = {

{0,0}, /* this point to be overwritten below */

{25,0}, {25,0}, {25,0}, {25,0}, {-100,25},

{25,0}, {25,0}, {25,0}, {25,0}, {-100,25},

{25,0}, {25,0}, {25,0}, {25,0}, {-100,25},

{25,0}, {25,0}, {25,0}, {25,0}, {-100,25},

{25,0}, {25,0}, {25,0}, {25,0}, {-100,25},

};

XSetForeground(display, gc, colors[RED ]);

736 XView Programming Manual

Example F-6. The x_draw.c program (continued)

XDrawString(display, xid, gc, 30, 20, "XFillRectangle", 14);

XFillRectangle(display, xid, gc, 25, 25, 100, 100);

XSetFunction(display, gc, GXinvert);

XFillRectangle(display, xid, gc, 50, 50, 50, 50);

XSetFunction(display, gc, GXcopy);

XSetForeground(display, gc, colors[BLACK]);

XDrawString(display, xid, gc, 155, 20, "XFillRect - stipple", 19);

XSetFillStyle(display, gc, FillStippled);

XFillRectangle(display, xid, gc, 150, 25, 100, 100);

XSetFillStyle(display, gc, FillSolid);

XSetForeground(display, gc, colors[BLUE]);

XDrawString(display, xid, gc, 280, 20, "XDrawPoints", 11);

points[0 ].x = 275; points[0].y = 25;

XDrawPoints(display, xid, gc, points,

sizeof(points)/sizeof(XPoint), CoordModePrevious);

XSetForeground(display, gc, colors[ORANGE]);

XDrawString(display, xid, gc, 30, 145, "XDrawLine - solid", 17);

XDrawLine(display, xid, gc, 25, 150, 125, 250);

XDrawLine(display, xid, gc, 25, 250, 125, 150);

XSetForeground(display, gc, colors[AQUA]);

XDrawString(display, xid, gc, 155, 145, "XDrawLine - dashed", 18);

XSetLineAttributes(display, gc, 5,

LineDoubleDash, CapButt, JoinMiter);

XDrawLine(display, xid, gc, 150, 150, 250, 250);

XDrawLine(display, xid, gc, 150, 250, 250, 150);

XSetLineAttributes(display, gc, 0, LineSolid, CapButt, JoinMiter);

XSetForeground(display, gc, colors[PINK]);

XDrawString(display, xid, gc, 280, 145, "XDrawLines", 10);

box[0 ].x = 275; box[0 ].y = 150;

XDrawLines(display, xid, gc, box, 5, CoordModePrevious);

XSetForeground(display, gc, colors[GREEN]);

XDrawRectangle(display, xid, gc,

5, 5, xv_get(pw, XV_WIDTH)-10, xv_get(pw, XV_HEIGHT)-10);

XDrawRectangle(display, xid, gc,

7, 7, xv_get(pw, XV_WIDTH)-14, xv_get(pw, XV_HEIGHT)-14);

}

Example Programs

Example Programs 737