/*
* tkCanvImg.c --
*
* This file implements image items for canvas widgets.
*
* Copyright (c) 1994 The Regents of the University of California.
* Copyright (c) 1994-1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution of
* this file, and for a DISCLAIMER OF ALL WARRANTIES.
*/
#include "tkInt.h"
#include "tkCanvas.h"
/*
* The structure below defines the record for each image item.
*/
typedef struct ImageItem {
Tk_Item header; /* Generic stuff that's the same for all
* types. MUST BE FIRST IN STRUCTURE. */
Tk_Canvas canvas; /* Canvas containing the image. */
double x, y; /* Coordinates of positioning point for
* image. */
Tk_Anchor anchor; /* Where to anchor image relative to (x,y). */
char *imageString; /* String describing -image option
* (malloc-ed). NULL means no image right
* now. */
char *activeImageString; /* String describing -activeimage option.
* NULL means no image right now. */
char *disabledImageString; /* String describing -disabledimage option.
* NULL means no image right now. */
Tk_Image image; /* Image to display in window, or NULL if no
* image at present. */
Tk_Image activeImage; /* Image to display in window, or NULL if no
* image at present. */
Tk_Image disabledImage; /* Image to display in window, or NULL if no
* image at present. */
} ImageItem;
/*
* Information used for parsing configuration specs:
*/
static const Tk_CustomOption stateOption = {
TkStateParseProc, TkStatePrintProc, INT2PTR(2)
};
static const Tk_CustomOption tagsOption = {
Tk_CanvasTagsParseProc, Tk_CanvasTagsPrintProc, NULL
};
static const Tk_ConfigSpec configSpecs[] = {
{TK_CONFIG_STRING, "-activeimage", NULL, NULL,
NULL, Tk_Offset(ImageItem, activeImageString), TK_CONFIG_NULL_OK, NULL},
{TK_CONFIG_ANCHOR, "-anchor", NULL, NULL,
"center", Tk_Offset(ImageItem, anchor), TK_CONFIG_DONT_SET_DEFAULT, NULL},
{TK_CONFIG_STRING, "-disabledimage", NULL, NULL,
NULL, Tk_Offset(ImageItem, disabledImageString), TK_CONFIG_NULL_OK, NULL},
{TK_CONFIG_STRING, "-image", NULL, NULL,
NULL, Tk_Offset(ImageItem, imageString), TK_CONFIG_NULL_OK, NULL},
{TK_CONFIG_CUSTOM, "-state", NULL, NULL,
NULL, Tk_Offset(Tk_Item, state), TK_CONFIG_NULL_OK, &stateOption},
{TK_CONFIG_CUSTOM, "-tags", NULL, NULL,
NULL, 0, TK_CONFIG_NULL_OK, &tagsOption},
{TK_CONFIG_END, NULL, NULL, NULL, NULL, 0, 0, NULL}
};
/*
* Prototypes for functions defined in this file:
*/
static void ImageChangedProc(ClientData clientData,
int x, int y, int width, int height, int imgWidth,
int imgHeight);
static int ImageCoords(Tcl_Interp *interp,
Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
Tcl_Obj *const argv[]);
static int ImageToArea(Tk_Canvas canvas,
Tk_Item *itemPtr, double *rectPtr);
static double ImageToPoint(Tk_Canvas canvas,
Tk_Item *itemPtr, double *coordPtr);
static int ImageToPostscript(Tcl_Interp *interp,
Tk_Canvas canvas, Tk_Item *itemPtr, int prepass);
static void ComputeImageBbox(Tk_Canvas canvas, ImageItem *imgPtr);
static int ConfigureImage(Tcl_Interp *interp,
Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
Tcl_Obj *const argv[], int flags);
static int CreateImage(Tcl_Interp *interp,
Tk_Canvas canvas, struct Tk_Item *itemPtr,
int argc, Tcl_Obj *const argv[]);
static void DeleteImage(Tk_Canvas canvas,
Tk_Item *itemPtr, Display *display);
static void DisplayImage(Tk_Canvas canvas,
Tk_Item *itemPtr, Display *display, Drawable dst,
int x, int y, int width, int height);
static void ScaleImage(Tk_Canvas canvas,
Tk_Item *itemPtr, double originX, double originY,
double scaleX, double scaleY);
static void TranslateImage(Tk_Canvas canvas,
Tk_Item *itemPtr, double deltaX, double deltaY);
/*
* The structures below defines the image item type in terms of functions that
* can be invoked by generic item code.
*/
Tk_ItemType tkImageType = {
"image", /* name */
sizeof(ImageItem), /* itemSize */
CreateImage, /* createProc */
configSpecs, /* configSpecs */
ConfigureImage, /* configureProc */
ImageCoords, /* coordProc */
DeleteImage, /* deleteProc */
DisplayImage, /* displayProc */
TK_CONFIG_OBJS, /* flags */
ImageToPoint, /* pointProc */
ImageToArea, /* areaProc */
ImageToPostscript, /* postscriptProc */
ScaleImage, /* scaleProc */
TranslateImage, /* translateProc */
NULL, /* indexProc */
NULL, /* icursorProc */
NULL, /* selectionProc */
NULL, /* insertProc */
NULL, /* dTextProc */
NULL, /* nextPtr */
NULL, 0, NULL, NULL
};
/*
*--------------------------------------------------------------
*
* CreateImage --
*
* This function is invoked to create a new image item in a canvas.
*
* Results:
* A standard Tcl return value. If an error occurred in creating the
* item, then an error message is left in the interp's result; in this
* case itemPtr is left uninitialized, so it can be safely freed by the
* caller.
*
* Side effects:
* A new image item is created.
*
*--------------------------------------------------------------
*/
static int
CreateImage(
Tcl_Interp *interp, /* Interpreter for error reporting. */
Tk_Canvas canvas, /* Canvas to hold new item. */
Tk_Item *itemPtr, /* Record to hold new item; header has been
* initialized by caller. */
int objc, /* Number of arguments in objv. */
Tcl_Obj *const objv[]) /* Arguments describing rectangle. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
int i;
if (objc == 0) {
Tcl_Panic("canvas did not pass any coords");
}
/*
* Initialize item's record.
*/
imgPtr->canvas = canvas;
imgPtr->anchor = TK_ANCHOR_CENTER;
imgPtr->imageString = NULL;
imgPtr->activeImageString = NULL;
imgPtr->disabledImageString = NULL;
imgPtr->image = NULL;
imgPtr->activeImage = NULL;
imgPtr->disabledImage = NULL;
/*
* Process the arguments to fill in the item record. Only 1 (list) or 2 (x
* y) coords are allowed.
*/
if (objc == 1) {
i = 1;
} else {
const char *arg = Tcl_GetString(objv[1]);
i = 2;
if ((arg[0] == '-') && (arg[1] >= 'a') && (arg[1] <= 'z')) {
i = 1;
}
}
if ((ImageCoords(interp, canvas, itemPtr, i, objv) != TCL_OK)) {
goto error;
}
if (ConfigureImage(interp, canvas, itemPtr, objc-i, objv+i, 0) == TCL_OK) {
return TCL_OK;
}
error:
DeleteImage(canvas, itemPtr, Tk_Display(Tk_CanvasTkwin(canvas)));
return TCL_ERROR;
}
/*
*--------------------------------------------------------------
*
* ImageCoords --
*
* This function is invoked to process the "coords" widget command on
* image items. See the user documentation for details on what it does.
*
* Results:
* Returns TCL_OK or TCL_ERROR, and sets the interp's result.
*
* Side effects:
* The coordinates for the given item may be changed.
*
*--------------------------------------------------------------
*/
static int
ImageCoords(
Tcl_Interp *interp, /* Used for error reporting. */
Tk_Canvas canvas, /* Canvas containing item. */
Tk_Item *itemPtr, /* Item whose coordinates are to be read or
* modified. */
int objc, /* Number of coordinates supplied in objv. */
Tcl_Obj *const objv[]) /* Array of coordinates: x1, y1, x2, y2, ... */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
if (objc == 0) {
Tcl_Obj *objs[2];
objs[0] = Tcl_NewDoubleObj(imgPtr->x);
objs[1] = Tcl_NewDoubleObj(imgPtr->y);
Tcl_SetObjResult(interp, Tcl_NewListObj(2, objs));
} else if (objc < 3) {
if (objc==1) {
if (Tcl_ListObjGetElements(interp, objv[0], &objc,
(Tcl_Obj ***) &objv) != TCL_OK) {
return TCL_ERROR;
} else if (objc != 2) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"wrong # coordinates: expected 2, got %d", objc));
Tcl_SetErrorCode(interp, "TK", "CANVAS", "COORDS", "IMAGE",
NULL);
return TCL_ERROR;
}
}
if ((Tk_CanvasGetCoordFromObj(interp, canvas, objv[0],
&imgPtr->x) != TCL_OK)
|| (Tk_CanvasGetCoordFromObj(interp, canvas, objv[1],
&imgPtr->y) != TCL_OK)) {
return TCL_ERROR;
}
ComputeImageBbox(canvas, imgPtr);
} else {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"wrong # coordinates: expected 0 or 2, got %d", objc));
Tcl_SetErrorCode(interp, "TK", "CANVAS", "COORDS", "IMAGE", NULL);
return TCL_ERROR;
}
return TCL_OK;
}
/*
*--------------------------------------------------------------
*
* ConfigureImage --
*
* This function is invoked to configure various aspects of an image
* item, such as its anchor position.
*
* Results:
* A standard Tcl result code. If an error occurs, then an error message
* is left in the interp's result.
*
* Side effects:
* Configuration information may be set for itemPtr.
*
*--------------------------------------------------------------
*/
static int
ConfigureImage(
Tcl_Interp *interp, /* Used for error reporting. */
Tk_Canvas canvas, /* Canvas containing itemPtr. */
Tk_Item *itemPtr, /* Image item to reconfigure. */
int objc, /* Number of elements in objv. */
Tcl_Obj *const objv[], /* Arguments describing things to configure. */
int flags) /* Flags to pass to Tk_ConfigureWidget. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
Tk_Window tkwin;
Tk_Image image;
tkwin = Tk_CanvasTkwin(canvas);
if (TCL_OK != Tk_ConfigureWidget(interp, tkwin, configSpecs, objc,
(const char **) objv, (char *) imgPtr, flags|TK_CONFIG_OBJS)) {
return TCL_ERROR;
}
/*
* Create the image. Save the old image around and don't free it until
* after the new one is allocated. This keeps the reference count from
* going to zero so the image doesn't have to be recreated if it hasn't
* changed.
*/
if (imgPtr->activeImageString != NULL) {
itemPtr->redraw_flags |= TK_ITEM_STATE_DEPENDANT;
} else {
itemPtr->redraw_flags &= ~TK_ITEM_STATE_DEPENDANT;
}
if (imgPtr->imageString != NULL) {
image = Tk_GetImage(interp, tkwin, imgPtr->imageString,
ImageChangedProc, imgPtr);
if (image == NULL) {
return TCL_ERROR;
}
} else {
image = NULL;
}
if (imgPtr->image != NULL) {
Tk_FreeImage(imgPtr->image);
}
imgPtr->image = image;
if (imgPtr->activeImageString != NULL) {
image = Tk_GetImage(interp, tkwin, imgPtr->activeImageString,
ImageChangedProc, imgPtr);
if (image == NULL) {
return TCL_ERROR;
}
} else {
image = NULL;
}
if (imgPtr->activeImage != NULL) {
Tk_FreeImage(imgPtr->activeImage);
}
imgPtr->activeImage = image;
if (imgPtr->disabledImageString != NULL) {
image = Tk_GetImage(interp, tkwin, imgPtr->disabledImageString,
ImageChangedProc, imgPtr);
if (image == NULL) {
return TCL_ERROR;
}
} else {
image = NULL;
}
if (imgPtr->disabledImage != NULL) {
Tk_FreeImage(imgPtr->disabledImage);
}
imgPtr->disabledImage = image;
ComputeImageBbox(canvas, imgPtr);
return TCL_OK;
}
/*
*--------------------------------------------------------------
*
* DeleteImage --
*
* This function is called to clean up the data structure associated with
* a image item.
*
* Results:
* None.
*
* Side effects:
* Resources associated with itemPtr are released.
*
*--------------------------------------------------------------
*/
static void
DeleteImage(
Tk_Canvas canvas, /* Info about overall canvas widget. */
Tk_Item *itemPtr, /* Item that is being deleted. */
Display *display) /* Display containing window for canvas. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
if (imgPtr->imageString != NULL) {
ckfree(imgPtr->imageString);
}
if (imgPtr->activeImageString != NULL) {
ckfree(imgPtr->activeImageString);
}
if (imgPtr->disabledImageString != NULL) {
ckfree(imgPtr->disabledImageString);
}
if (imgPtr->image != NULL) {
Tk_FreeImage(imgPtr->image);
}
if (imgPtr->activeImage != NULL) {
Tk_FreeImage(imgPtr->activeImage);
}
if (imgPtr->disabledImage != NULL) {
Tk_FreeImage(imgPtr->disabledImage);
}
}
/*
*--------------------------------------------------------------
*
* ComputeImageBbox --
*
* This function is invoked to compute the bounding box of all the pixels
* that may be drawn as part of a image item. This function is where the
* child image's placement is computed.
*
* Results:
* None.
*
* Side effects:
* The fields x1, y1, x2, and y2 are updated in the header for itemPtr.
*
*--------------------------------------------------------------
*/
/* ARGSUSED */
static void
ComputeImageBbox(
Tk_Canvas canvas, /* Canvas that contains item. */
ImageItem *imgPtr) /* Item whose bbox is to be recomputed. */
{
int width, height;
int x, y;
Tk_Image image;
Tk_State state = imgPtr->header.state;
if(state == TK_STATE_NULL) {
state = Canvas(canvas)->canvas_state;
}
image = imgPtr->image;
if (Canvas(canvas)->currentItemPtr == (Tk_Item *)imgPtr) {
if (imgPtr->activeImage != NULL) {
image = imgPtr->activeImage;
}
} else if (state == TK_STATE_DISABLED) {
if (imgPtr->disabledImage != NULL) {
image = imgPtr->disabledImage;
}
}
x = (int) (imgPtr->x + ((imgPtr->x >= 0) ? 0.5 : - 0.5));
y = (int) (imgPtr->y + ((imgPtr->y >= 0) ? 0.5 : - 0.5));
if ((state == TK_STATE_HIDDEN) || (image == None)) {
imgPtr->header.x1 = imgPtr->header.x2 = x;
imgPtr->header.y1 = imgPtr->header.y2 = y;
return;
}
/*
* Compute location and size of image, using anchor information.
*/
Tk_SizeOfImage(image, &width, &height);
switch (imgPtr->anchor) {
case TK_ANCHOR_N:
x -= width/2;
break;
case TK_ANCHOR_NE:
x -= width;
break;
case TK_ANCHOR_E:
x -= width;
y -= height/2;
break;
case TK_ANCHOR_SE:
x -= width;
y -= height;
break;
case TK_ANCHOR_S:
x -= width/2;
y -= height;
break;
case TK_ANCHOR_SW:
y -= height;
break;
case TK_ANCHOR_W:
y -= height/2;
break;
case TK_ANCHOR_NW:
break;
case TK_ANCHOR_CENTER:
x -= width/2;
y -= height/2;
break;
}
/*
* Store the information in the item header.
*/
imgPtr->header.x1 = x;
imgPtr->header.y1 = y;
imgPtr->header.x2 = x + width;
imgPtr->header.y2 = y + height;
}
/*
*--------------------------------------------------------------
*
* DisplayImage --
*
* This function is invoked to draw a image item in a given drawable.
*
* Results:
* None.
*
* Side effects:
* ItemPtr is drawn in drawable using the transformation information in
* canvas.
*
*--------------------------------------------------------------
*/
static void
DisplayImage(
Tk_Canvas canvas, /* Canvas that contains item. */
Tk_Item *itemPtr, /* Item to be displayed. */
Display *display, /* Display on which to draw item. */
Drawable drawable, /* Pixmap or window in which to draw item. */
int x, int y, int width, int height)
/* Describes region of canvas that must be
* redisplayed (not used). */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
short drawableX, drawableY;
Tk_Image image;
Tk_State state = itemPtr->state;
if (state == TK_STATE_NULL) {
state = Canvas(canvas)->canvas_state;
}
image = imgPtr->image;
if (Canvas(canvas)->currentItemPtr == itemPtr) {
if (imgPtr->activeImage != NULL) {
image = imgPtr->activeImage;
}
} else if (state == TK_STATE_DISABLED) {
if (imgPtr->disabledImage != NULL) {
image = imgPtr->disabledImage;
}
}
if (image == NULL) {
return;
}
/*
* Translate the coordinates to those of the image, then redisplay it.
*/
Tk_CanvasDrawableCoords(canvas, (double) x, (double) y,
&drawableX, &drawableY);
Tk_RedrawImage(image, x - imgPtr->header.x1, y - imgPtr->header.y1,
width, height, drawable, drawableX, drawableY);
}
/*
*--------------------------------------------------------------
*
* ImageToPoint --
*
* Computes the distance from a given point to a given rectangle, in
* canvas units.
*
* Results:
* The return value is 0 if the point whose x and y coordinates are
* coordPtr[0] and coordPtr[1] is inside the image. If the point isn't
* inside the image then the return value is the distance from the point
* to the image.
*
* Side effects:
* None.
*
*--------------------------------------------------------------
*/
static double
ImageToPoint(
Tk_Canvas canvas, /* Canvas containing item. */
Tk_Item *itemPtr, /* Item to check against point. */
double *coordPtr) /* Pointer to x and y coordinates. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
double x1, x2, y1, y2, xDiff, yDiff;
x1 = imgPtr->header.x1;
y1 = imgPtr->header.y1;
x2 = imgPtr->header.x2;
y2 = imgPtr->header.y2;
/*
* Point is outside rectangle.
*/
if (coordPtr[0] < x1) {
xDiff = x1 - coordPtr[0];
} else if (coordPtr[0] > x2) {
xDiff = coordPtr[0] - x2;
} else {
xDiff = 0;
}
if (coordPtr[1] < y1) {
yDiff = y1 - coordPtr[1];
} else if (coordPtr[1] > y2) {
yDiff = coordPtr[1] - y2;
} else {
yDiff = 0;
}
return hypot(xDiff, yDiff);
}
/*
*--------------------------------------------------------------
*
* ImageToArea --
*
* This function is called to determine whether an item lies entirely
* inside, entirely outside, or overlapping a given rectangle.
*
* Results:
* -1 is returned if the item is entirely outside the area given by
* rectPtr, 0 if it overlaps, and 1 if it is entirely inside the given
* area.
*
* Side effects:
* None.
*
*--------------------------------------------------------------
*/
static int
ImageToArea(
Tk_Canvas canvas, /* Canvas containing item. */
Tk_Item *itemPtr, /* Item to check against rectangle. */
double *rectPtr) /* Pointer to array of four coordinates
* (x1,y1,x2,y2) describing rectangular
* area. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
if ((rectPtr[2] <= imgPtr->header.x1)
|| (rectPtr[0] >= imgPtr->header.x2)
|| (rectPtr[3] <= imgPtr->header.y1)
|| (rectPtr[1] >= imgPtr->header.y2)) {
return -1;
}
if ((rectPtr[0] <= imgPtr->header.x1)
&& (rectPtr[1] <= imgPtr->header.y1)
&& (rectPtr[2] >= imgPtr->header.x2)
&& (rectPtr[3] >= imgPtr->header.y2)) {
return 1;
}
return 0;
}
/*
*--------------------------------------------------------------
*
* ImageToPostscript --
*
* This function is called to generate Postscript for image items.
*
* Results:
* The return value is a standard Tcl result. If an error occurs in
* generating Postscript then an error message is left in interp->result,
* replacing whatever used to be there. If no error occurs, then
* Postscript for the item is appended to the result.
*
* Side effects:
* None.
*
*--------------------------------------------------------------
*/
static int
ImageToPostscript(
Tcl_Interp *interp, /* Leave Postscript or error message here. */
Tk_Canvas canvas, /* Information about overall canvas. */
Tk_Item *itemPtr, /* Item for which Postscript is wanted. */
int prepass) /* 1 means this is a prepass to collect font
* information; 0 means final Postscript is
* being created.*/
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
Tk_Window canvasWin = Tk_CanvasTkwin(canvas);
double x, y;
int width, height;
Tk_Image image;
Tk_State state = itemPtr->state;
if (state == TK_STATE_NULL) {
state = Canvas(canvas)->canvas_state;
}
image = imgPtr->image;
if (Canvas(canvas)->currentItemPtr == itemPtr) {
if (imgPtr->activeImage != NULL) {
image = imgPtr->activeImage;
}
} else if (state == TK_STATE_DISABLED) {
if (imgPtr->disabledImage != NULL) {
image = imgPtr->disabledImage;
}
}
if (image == NULL) {
/*
* Image item without actual image specified.
*/
return TCL_OK;
}
Tk_SizeOfImage(image, &width, &height);
/*
* Compute the coordinates of the lower-left corner of the image, taking
* into account the anchor position for the image.
*/
x = imgPtr->x;
y = Tk_CanvasPsY(canvas, imgPtr->y);
switch (imgPtr->anchor) {
case TK_ANCHOR_NW: y -= height; break;
case TK_ANCHOR_N: x -= width/2.0; y -= height; break;
case TK_ANCHOR_NE: x -= width; y -= height; break;
case TK_ANCHOR_E: x -= width; y -= height/2.0; break;
case TK_ANCHOR_SE: x -= width; break;
case TK_ANCHOR_S: x -= width/2.0; break;
case TK_ANCHOR_SW: break;
case TK_ANCHOR_W: y -= height/2.0; break;
case TK_ANCHOR_CENTER: x -= width/2.0; y -= height/2.0; break;
}
if (!prepass) {
Tcl_Obj *psObj = Tcl_GetObjResult(interp);
if (Tcl_IsShared(psObj)) {
psObj = Tcl_DuplicateObj(psObj);
Tcl_SetObjResult(interp, psObj);
}
Tcl_AppendPrintfToObj(psObj, "%.15g %.15g translate\n", x, y);
}
return Tk_PostscriptImage(image, interp, canvasWin,
((TkCanvas *) canvas)->psInfo, 0, 0, width, height, prepass);
}
/*
*--------------------------------------------------------------
*
* ScaleImage --
*
* This function is invoked to rescale an item.
*
* Results:
* None.
*
* Side effects:
* The item referred to by itemPtr is rescaled so that the following
* transformation is applied to all point coordinates:
* x' = originX + scaleX*(x-originX)
* y' = originY + scaleY*(y-originY)
*
*--------------------------------------------------------------
*/
static void
ScaleImage(
Tk_Canvas canvas, /* Canvas containing rectangle. */
Tk_Item *itemPtr, /* Rectangle to be scaled. */
double originX, double originY,
/* Origin about which to scale rect. */
double scaleX, /* Amount to scale in X direction. */
double scaleY) /* Amount to scale in Y direction. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
imgPtr->x = originX + scaleX*(imgPtr->x - originX);
imgPtr->y = originY + scaleY*(imgPtr->y - originY);
ComputeImageBbox(canvas, imgPtr);
}
/*
*--------------------------------------------------------------
*
* TranslateImage --
*
* This function is called to move an item by a given amount.
*
* Results:
* None.
*
* Side effects:
* The position of the item is offset by (xDelta, yDelta), and the
* bounding box is updated in the generic part of the item structure.
*
*--------------------------------------------------------------
*/
static void
TranslateImage(
Tk_Canvas canvas, /* Canvas containing item. */
Tk_Item *itemPtr, /* Item that is being moved. */
double deltaX, double deltaY)
/* Amount by which item is to be moved. */
{
ImageItem *imgPtr = (ImageItem *) itemPtr;
imgPtr->x += deltaX;
imgPtr->y += deltaY;
ComputeImageBbox(canvas, imgPtr);
}
/*
*----------------------------------------------------------------------
*
* ImageChangedProc --
*
* This function is invoked by the image code whenever the manager for an
* image does something that affects the image's size or how it is
* displayed.
*
* Results:
* None.
*
* Side effects:
* Arranges for the canvas to get redisplayed.
*
*----------------------------------------------------------------------
*/
static void
ImageChangedProc(
ClientData clientData, /* Pointer to canvas item for image. */
int x, int y, /* Upper left pixel (within image) that must
* be redisplayed. */
int width, int height, /* Dimensions of area to redisplay (may be <=
* 0). */
int imgWidth, int imgHeight)/* New dimensions of image. */
{
ImageItem *imgPtr = clientData;
/*
* If the image's size changed and it's not anchored at its northwest
* corner then just redisplay the entire area of the image. This is a bit
* over-conservative, but we need to do something because a size change
* also means a position change.
*/
if (((imgPtr->header.x2 - imgPtr->header.x1) != imgWidth)
|| ((imgPtr->header.y2 - imgPtr->header.y1) != imgHeight)) {
x = y = 0;
width = imgWidth;
height = imgHeight;
Tk_CanvasEventuallyRedraw(imgPtr->canvas, imgPtr->header.x1,
imgPtr->header.y1, imgPtr->header.x2, imgPtr->header.y2);
}
ComputeImageBbox(imgPtr->canvas, imgPtr);
Tk_CanvasEventuallyRedraw(imgPtr->canvas, imgPtr->header.x1 + x,
imgPtr->header.y1 + y, (int) (imgPtr->header.x1 + x + width),
(int) (imgPtr->header.y1 + y + height));
}
/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* End:
*/