Tk Source Code

Check-in [ec97c557]
Login
Bounty program for improvements to Tcl and certain Tcl packages.
Tcl 2019 Conference, Houston/TX, US, Nov 4-8
Send your abstracts to [email protected]
or submit via the online form by Sep 9.

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Reformat some lines - Better follow the Tcl Engineering Manual
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | canvas_image | tip-489
Files: files | file ages | folders
SHA3-256: ec97c55744c5f2b6cc1362592195365c50fc2e70d558592b8526b203653fe676
User & Date: fvogel 2018-02-10 15:29:29
Context
2018-02-10
15:36
Fix formatting in man canvas for the image command check-in: 1633e545 user: fvogel tags: canvas_image, tip-489
15:29
Reformat some lines - Better follow the Tcl Engineering Manual check-in: ec97c557 user: fvogel tags: canvas_image, tip-489
14:53
merge core-8-6-branch check-in: a3f9d6bd user: fvogel tags: canvas_image, tip-489
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to generic/tkCanvas.c.

2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154

2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167

2168
2169
2170
2171
2172
2173
2174
....
2483
2484
2485
2486
2487
2488
2489

2490
2491
2492
2493
2494
2495
2496
2497
2498
2499

2500
2501
2502
2503
2504
2505
2506
2507
2508
2509

2510
2511
2512
2513
2514
2515
2516
....
2530
2531
2532
2533
2534
2535
2536
2537


2538
2539

2540
2541
2542
2543
2544
2545
2546
....
2559
2560
2561
2562
2563
2564
2565

2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580

2581
2582
2583
2584
2585
2586
2587
....
2608
2609
2610
2611
2612
2613
2614

2615

2616
2617
2618
2619
2620
2621
2622
2623
2624

2625
2626

2627
2628

2629
2630
2631
2632
2633
2634
2635
....
2641
2642
2643
2644
2645
2646
2647
2648

2649
2650

2651
2652
2653
2654
2655
2656
2657

2658
2659
2660
2661
2662
2663
2664

2665

2666
2667
2668
2669
2670
2671
2672
2673

2674
2675
2676

2677

2678
2679
2680
2681

2682

2683
2684
2685

2686
2687
2688
2689
2690
2691

2692

2693

2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707

2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744

2745
2746

2747
2748
2749

2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761

2762

2763
2764
2765

2766
2767
2768
2769
2770
2771
2772
2773
2774

2775

2776



2777
2778

2779
2780
2781

2782
2783

2784
2785
2786
2787
2788

2789
2790

2791
2792
2793
2794

2795

2796
2797


2798
2799
2800
2801
2802
2803

2804

2805
2806


2807
2808
2809
2810
2811
2812
2813

2814

2815

2816

2817

2818

2819
2820
2821
2822
2823
2824
2825
2826

2827

2828

2829

2830
2831
2832
2833
2834
2835
2836
2837
2838


2839
2840
2841
2842


2843
2844
2845
2846


2847
2848
2849

2850
2851
2852
2853

2854
2855



2856
2857
2858
2859

2860
2861
2862
2863
2864
2865
2866

2867
2868
2869
2870
2871
2872
2873
	break;
    }
    case CANV_IMAGE: {
        Tk_PhotoHandle photohandle;
        int subsample = 1, zoom = 1;

        if (objc < 3 && objc > 5) {
            Tcl_WrongNumArgs(interp, 2, objv, "imagename | image imagename subsample | image imagename subsample zoom");
            result = TCL_ERROR;
            goto done;
        }

        if ((photohandle = Tk_FindPhoto(interp, Tcl_GetString(objv[2]) )) == 0) {
            result = TCL_ERROR;
            goto done;
        }

        /*
         * If we are given a subsample or a zoom then grab them.
         */

        if (objc >= 4 && Tcl_GetIntFromObj(interp, objv[3], &subsample) != TCL_OK) {
            result = TCL_ERROR;
            goto done;
        }
        if (objc >= 5 && Tcl_GetIntFromObj(interp, objv[4], &zoom) != TCL_OK) {
            result = TCL_ERROR;
            goto done;
        }

        /*
         * Set the image size to zero, which allows the DrawCanvas() function to expand the image automatically when
         * it copies the pixmap into it.
         */

        if (Tk_PhotoSetSize(interp, photohandle, 0, 0) != TCL_OK) {
            result = TCL_ERROR;
            goto done;
        }

        result = DrawCanvas(interp, clientData, photohandle, subsample, zoom);
    }
................................................................................
    
    *shift = 0;
    *bits = 0;
    
    /*
     * Find the lowest '1' bit in the mask.
     */

    for (i = 0; i < 32; ++i) {
        if (mask & 1 << i)
            break;
    }
    if (i < 32) {
        *shift = i;
        
        /*
        * Now find the next '0' bit and the width of the mask.
        */

        for ( ; i < 32; ++i) {
            if ((mask & 1 << i) == 0)
                break;
            else
                ++*bits;
        }
        
        /*
        * Limit to the top 8 bits if the mask was wider than 8.
        */

        if (*bits > 8) {
            *shift += *bits - 8;
            *bits = 8;
        }
    }
}

................................................................................
 * Side effects:
 *      Canvas contents from within the -scrollregion or widget size are rendered
 *      into the Photo. Any errors are left in the result.
 *
 *----------------------------------------------------------------------
 */

#define OVERDRAW_PIXELS 32        /* How much larger we make the pixmap that the canvas objects are drawn into */


/* From stackoverflow.com/questions/2100331/c-macro-definition-to-determine-big-endian-or-little-endian-machine */
#define IS_BIG_ENDIAN (*(unsigned short *)"\0\xff" < 0x100)

#define BYTE_SWAP16(n) ((((unsigned short)n)>>8) | (((unsigned short)n)<<8))
#define BYTE_SWAP32(n) (((n>>24)&0x000000FF) | ((n<<8)&0x00FF0000) | ((n>>8)&0x0000FF00) | ((n<<24)&0xFF000000))

static int
DrawCanvas(
    Tcl_Interp *interp,           /* As passed to the widget command, and we will leave errors here */
    ClientData clientData,
................................................................................
    Visual *visualPtr;
    GC xgc = 0;
    XGCValues xgcValues;
    int canvasX1, canvasY1, canvasX2, canvasY2, cWidth, cHeight,
        pixmapX1, pixmapY1, pixmapX2, pixmapY2, pmWidth, pmHeight,
        bitsPerPixel, bytesPerPixel, x, y, result = TCL_OK,
        rshift, gshift, bshift, rbits, gbits, bbits;

#ifdef DEBUG_DRAWCANVAS
    char buffer[128];
#endif

    if ((tkwin = canvasPtr->tkwin) == NULL) {
        Tcl_AppendResult(interp, "canvas tkwin is NULL!", NULL);
        result = TCL_ERROR;
        goto done;
    }

    /*
     * If this canvas is unmapped, then we won't have a window id, so we will try
     * the ancestors of the canvas until we find a window that has a valid window id.
     * The Tk_GetPixmap() call requires a valid window id.
     */

    do {

        if ((displayPtr = Tk_Display(tkwin)) == NULL) {
            Tcl_AppendResult(interp, "canvas (or parent) display is NULL!", NULL);
            result = TCL_ERROR;
            goto done;
        }
................................................................................
    }

    /*
    * Scan through the item list, registering the bounding box for all items
    * that didn't do that for the final coordinates yet. This can be
    * determined by the FORCE_REDRAW flag.
    */

    for (itemPtr = canvasPtr -> firstItemPtr; itemPtr != NULL; itemPtr = itemPtr -> nextPtr) {

        if (itemPtr -> redraw_flags & FORCE_REDRAW) {
            itemPtr -> redraw_flags &= ~FORCE_REDRAW;
            EventuallyRedrawItem(canvasPtr, itemPtr);
            itemPtr -> redraw_flags &= ~FORCE_REDRAW;
        }
    }

    /*
     * The DisplayCanvas() function works out the region that needs redrawing, but we don't do this. We grab the whole

     * scrollregion or canvas window area. If we have a defined -scrollregion we use that as the drawing region, otherwise
     * use the canvas window height and width with an origin of 0,0.

     */
    if (canvasPtr->scrollX1 != 0 || canvasPtr->scrollY1 != 0 || canvasPtr->scrollX2 != 0 || canvasPtr->scrollY2 != 0) {


        canvasX1 = canvasPtr->scrollX1;
        canvasY1 = canvasPtr->scrollY1;
        canvasX2 = canvasPtr->scrollX2;
        canvasY2 = canvasPtr->scrollY2;
        cWidth = canvasX2 - canvasX1 + 1;
        cHeight = canvasY2 - canvasY1 + 1;
................................................................................
        canvasX1 = 0;
        canvasY1 = 0;
        canvasX2 = canvasX1 + cWidth - 1;
        canvasY2 = canvasY1 + cHeight - 1;
    }
    
    /*
     * Allocate a pixmap to draw into. We add OVERDRAW_PIXELS in the same way that DisplayCanvas() does

     * to avoid problems on some systems when objects are being drawn too close to the edge.
     */

    pixmapX1 = canvasX1 - OVERDRAW_PIXELS;
    pixmapY1 = canvasY1 - OVERDRAW_PIXELS;
    pixmapX2 = canvasX2 + OVERDRAW_PIXELS;
    pixmapY2 = canvasY2 + OVERDRAW_PIXELS;
    pmWidth = pixmapX2 - pixmapX1 + 1;
    pmHeight = pixmapY2 - pixmapY1 + 1;
    if ((pixmap = Tk_GetPixmap(displayPtr, Tk_WindowId(tkwin), pmWidth, pmHeight, bitsPerPixel)) == 0) {

        Tcl_AppendResult(interp, "failed to create drawing Pixmap", NULL);
        result = TCL_ERROR;
        goto done;
    }

    /*
     * Before we can draw the canvas objects into the pixmap it's background should be filled with canvas background colour.

     */

    xgcValues.function = GXcopy;
    xgcValues.foreground = Tk_3DBorderColor(canvasPtr->bgBorder)->pixel;
    xgc = XCreateGC(displayPtr, pixmap, GCFunction|GCForeground, &xgcValues);
    XFillRectangle(displayPtr,pixmap,xgc,0,0,pmWidth,pmHeight);

    /*
     * Draw all the cavas items into the pixmap
     */

    canvasPtr->drawableXOrigin = pixmapX1;
    canvasPtr->drawableYOrigin = pixmapY1;
    for (itemPtr = canvasPtr->firstItemPtr; itemPtr != NULL; itemPtr = itemPtr->nextPtr) {

        if ((itemPtr->x1 >= pixmapX2) || (itemPtr->y1 >= pixmapY2) || (itemPtr->x2 < pixmapX1) || (itemPtr->y2 < pixmapY1)) {

            if (!AlwaysRedraw(itemPtr)) {
                continue;
            }
        }

        if (itemPtr -> state == TK_STATE_HIDDEN || (itemPtr -> state == TK_STATE_NULL && canvasPtr -> canvas_state == TK_STATE_HIDDEN)) {

            continue;
        }
        ItemDisplay(canvasPtr, itemPtr, pixmap, pixmapX1, pixmapY1, pmWidth, pmHeight);

    }
    
    /*
     * Copy the Pixmap into an ZPixmap format XImage so we can copy it across to the photo image.
     * This seems to be the only way to get Pixmap image data out of an image.
     * Note we have to account for the OVERDRAW_PIXELS border width.

     */

    if ((ximagePtr = XGetImage(displayPtr,pixmap,-pixmapX1,-pixmapY1,cWidth,cHeight,AllPlanes,ZPixmap)) == NULL) {

        Tcl_AppendResult(interp, "failed to copy Pixmap to XImage", NULL);
        result = TCL_ERROR;
        goto done;
    }
    
#ifdef DEBUG_DRAWCANVAS
    Tcl_AppendResult(interp, "ximagePtr {", NULL);
    sprintf(buffer,"%d",ximagePtr->width);              Tcl_AppendResult(interp, " width ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->height);             Tcl_AppendResult(interp, " height ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->xoffset);            Tcl_AppendResult(interp, " xoffset ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->format);             Tcl_AppendResult(interp, " format ", buffer, NULL);
                                                        Tcl_AppendResult(interp, " ximagePtr->data", NULL);
    if (ximagePtr->data != NULL) {
		int ix, iy;

		Tcl_AppendResult(interp, " {", NULL);
		for (iy = 0; iy < ximagePtr->height; ++ iy) {
			Tcl_AppendResult(interp, " {", NULL);
			for (ix = 0; ix < ximagePtr->bytes_per_line; ++ ix) {
				if (ix > 0) {
                    if (ix % 4 == 0)
                        Tcl_AppendResult(interp, "-", NULL);
                    else
                        Tcl_AppendResult(interp, " ", NULL);
                }
				sprintf(buffer,"%2.2x",ximagePtr->data[ximagePtr->bytes_per_line * iy + ix]&0xFF);
				Tcl_AppendResult(interp, buffer, NULL);
			}
			Tcl_AppendResult(interp, " }", NULL);
		}
		Tcl_AppendResult(interp, " }", NULL);
	} else
		sprintf(buffer," NULL");
    sprintf(buffer,"%d",ximagePtr->byte_order);         Tcl_AppendResult(interp, " byte_order ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bitmap_unit);        Tcl_AppendResult(interp, " bitmap_unit ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bitmap_bit_order);   Tcl_AppendResult(interp, " bitmap_bit_order ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bitmap_pad);         Tcl_AppendResult(interp, " bitmap_pad ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->depth);              Tcl_AppendResult(interp, " depth ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bytes_per_line);     Tcl_AppendResult(interp, " bytes_per_line ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bits_per_pixel);     Tcl_AppendResult(interp, " bits_per_pixel ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",ximagePtr->red_mask);      Tcl_AppendResult(interp, " red_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",ximagePtr->green_mask);    Tcl_AppendResult(interp, " green_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",ximagePtr->blue_mask);     Tcl_AppendResult(interp, " blue_mask ", buffer, NULL);
    Tcl_AppendResult(interp, " }", NULL);
    
    Tcl_AppendResult(interp, "\nvisualPtr {", NULL);
    sprintf(buffer,"0x%8.8lx",visualPtr->red_mask);      Tcl_AppendResult(interp, " red_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",visualPtr->green_mask);    Tcl_AppendResult(interp, " green_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",visualPtr->blue_mask);     Tcl_AppendResult(interp, " blue_mask ", buffer, NULL);
    Tcl_AppendResult(interp, " }", NULL);
    
#endif

    /*
     * Fill in the PhotoImageBlock structure abd allocate a block of memory for the converted image data.

     * Note we allocate an alpha channel even though we don't use one, because this layout helps Tk_PhotoPutBlock()
     * use memcpy() instead of the slow pixel or line copy.
     */

    blockPtr.width = cWidth;
    blockPtr.height = cHeight;
    blockPtr.pixelSize = 4;
    blockPtr.pitch = blockPtr.pixelSize * blockPtr.width;
    blockPtr.offset[0] = 0;
    blockPtr.offset[1] = 1;
    blockPtr.offset[2] = 2;
    blockPtr.offset[3] = 3;
    blockPtr.pixelPtr = ckalloc(blockPtr.pixelSize * blockPtr.height * blockPtr.width);

    /*
     * Now convert the image data pixel by pixel from XImage to 32bit RGBA format suitable for Tk_PhotoPutBlock().

     */

    DecomposeMaskToShiftAndBits(visualPtr->red_mask,&rshift,&rbits);
    DecomposeMaskToShiftAndBits(visualPtr->green_mask,&gshift,&gbits);
    DecomposeMaskToShiftAndBits(visualPtr->blue_mask,&bshift,&bbits);

#ifdef DEBUG_DRAWCANVAS
    sprintf(buffer,"%d",rshift);  Tcl_AppendResult(interp, "\nbits { rshift ", buffer, NULL);
    sprintf(buffer,"%d",gshift);  Tcl_AppendResult(interp, " gshift ", buffer, NULL);
    sprintf(buffer,"%d",bshift);  Tcl_AppendResult(interp, " bshift ", buffer, NULL);
    sprintf(buffer,"%d",rbits);   Tcl_AppendResult(interp, " rbits ", buffer, NULL);
    sprintf(buffer,"%d",gbits);   Tcl_AppendResult(interp, " gbits ", buffer, NULL);
    sprintf(buffer,"%d",bbits);   Tcl_AppendResult(interp, " bbits ", buffer, " }", NULL);
    Tcl_AppendResult(interp, "\nConverted_image {", NULL);
#endif

    /* SVP: Ok I had to use ximagePtr->bits_per_pixel here and in the switch (...) below to get this to work on Windows. X11 correctly

     * sets the bitmap_pad and bitmap_unit fields to 32, but on Windows they are 0 and 8 respectively! */



    bytesPerPixel = ximagePtr->bits_per_pixel/8;
    for (y = 0; y < blockPtr.height; ++y) {

#ifdef DEBUG_DRAWCANVAS
        Tcl_AppendResult(interp, " {", NULL);
#endif

        for(x = 0; x < blockPtr.width; ++x) {
            unsigned long pixel;

			switch (ximagePtr->bits_per_pixel) {

                /*
                 * Get an 8 bit pixel from the XImage.
                 */

                case 8 :
                   pixel = *((unsigned char *)(ximagePtr->data + bytesPerPixel * x + ximagePtr->bytes_per_line * y));

                    break;

                /*
                 * Get a 16 bit pixel from the XImage, and correct the byte order as necessary.

                 */

                case 16 :
                    pixel = *((unsigned short *)(ximagePtr->data + bytesPerPixel * x + ximagePtr->bytes_per_line * y));


                    if ((IS_BIG_ENDIAN && ximagePtr->byte_order == LSBFirst) || (!IS_BIG_ENDIAN && ximagePtr->byte_order == MSBFirst))
                        pixel = BYTE_SWAP16(pixel);
                    break;

                /*
                 * Grab a 32 bit pixel from the XImage, and correct the byte order as necessary.

                 */

                case 32 :
                    pixel = *((unsigned long *)(ximagePtr->data + bytesPerPixel * x + ximagePtr->bytes_per_line * y));


                    if ((IS_BIG_ENDIAN && ximagePtr->byte_order == LSBFirst) || (!IS_BIG_ENDIAN && ximagePtr->byte_order == MSBFirst))
                        pixel = BYTE_SWAP32(pixel);
                    break;
            }

            /*
             * We have a pixel with the correct byte order, so pull out the colours and place them in the photo block.

             * Perhaps we could just not bother with the alpha byte because we are using TK_PHOTO_COMPOSITE_SET later?

             * ***Windows: We have to swap the red and blue values. The XImage storage is B - G - R - A which becomes a

             * 32bit ARGB quad. However the visual mask is a 32bit ABGR quad. And Tk_PhotoPutBlock() wants R-G-B-A which is

             * a 32bit ABGR quad. If the visual mask was correct there would be no need to swap anything here.

             */

#ifdef _WIN32
#define   R_OFFSET 2
#define   B_OFFSET 0
#else
#define   R_OFFSET 0
#define   B_OFFSET 2
#endif
            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x + R_OFFSET] = (unsigned char)((pixel & visualPtr->red_mask) >> rshift);

            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x +1] = (unsigned char)((pixel & visualPtr->green_mask) >> gshift);

            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x + B_OFFSET] = (unsigned char)((pixel & visualPtr->blue_mask) >> bshift);

            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x +3] = 0xFF;

#ifdef DEBUG_DRAWCANVAS
            {
				int ix;
                if (x > 0)
                    Tcl_AppendResult(interp, "-", NULL);
				for (ix = 0; ix < 4; ++ix) {
                    if (ix > 0)
                        Tcl_AppendResult(interp, " ", NULL);
					sprintf(buffer,"%2.2x",blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x + ix]&0xFF); Tcl_AppendResult(interp, buffer, NULL);


                }
            }
#endif
        }


#ifdef DEBUG_DRAWCANVAS
        Tcl_AppendResult(interp, " }", NULL);
#endif
    }


#ifdef DEBUG_DRAWCANVAS
    Tcl_AppendResult(interp, " }", NULL);
#endif

    /*
     * Now put the copied pixmap into the photo.
     * If either zoom or subsample are not 1, we use the zoom function.
     */

    if (subsample != 1 || zoom != 1) {
        if ((result = Tk_PhotoPutZoomedBlock(interp, photohandle, &blockPtr, 0, 0, cWidth * zoom / subsample, cHeight * zoom / subsample, zoom, zoom, subsample, subsample, TK_PHOTO_COMPOSITE_SET)) != TCL_OK) {



            goto done;
        }
    } else {
        if ((result = Tk_PhotoPutBlock(interp, photohandle, &blockPtr, 0, 0, cWidth, cHeight, TK_PHOTO_COMPOSITE_SET)) != TCL_OK) {

            goto done;
        }
    }

    /*
     * Clean up anything we have allocated and exit.
     */

done:
    if (blockPtr.pixelPtr)
        ckfree(blockPtr.pixelPtr);
    if (pixmap)
        Tk_FreePixmap(Tk_Display(tkwin), pixmap);
    if (ximagePtr)
        XDestroyImage(ximagePtr);






|












>










|
|

>







 







>










>










>







 







|
>
>


>







 







>











|
|
|

>







 







>
|
>








|
>
|
|
>

|
>







 







|
>
|

>






|
>






|
>

>








>


|
>
|
>




>
|
>


|
>



|
|
|
>

>
|
>







|
|
|
|
|

|
>
|
|
|
|
|





|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|



|
|
|



>

|
>
|


>











|
>

>



>

|
|
|
|
|
|


>
|
>
|
>
>
>


>



>


>
|




>

|
>



|
>

>

|
>
>
|




|
>

>

|
>
>
|





|
>
|
>
|
>
|
>
|
>

>







|
>
|
>
|
>

>


|


|


|
>
>



|
>
>



|
>
>



>




>

|
>
>
>



|
>







>







2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
....
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
....
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
....
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
....
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
....
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
	break;
    }
    case CANV_IMAGE: {
        Tk_PhotoHandle photohandle;
        int subsample = 1, zoom = 1;

        if (objc < 3 && objc > 5) {
            Tcl_WrongNumArgs(interp, 2, objv, "imagename ?subsample? ?zoom?");
            result = TCL_ERROR;
            goto done;
        }

        if ((photohandle = Tk_FindPhoto(interp, Tcl_GetString(objv[2]) )) == 0) {
            result = TCL_ERROR;
            goto done;
        }

        /*
         * If we are given a subsample or a zoom then grab them.
         */

        if (objc >= 4 && Tcl_GetIntFromObj(interp, objv[3], &subsample) != TCL_OK) {
            result = TCL_ERROR;
            goto done;
        }
        if (objc >= 5 && Tcl_GetIntFromObj(interp, objv[4], &zoom) != TCL_OK) {
            result = TCL_ERROR;
            goto done;
        }

        /*
         * Set the image size to zero, which allows the DrawCanvas() function
         * to expand the image automatically when it copies the pixmap into it.
         */

        if (Tk_PhotoSetSize(interp, photohandle, 0, 0) != TCL_OK) {
            result = TCL_ERROR;
            goto done;
        }

        result = DrawCanvas(interp, clientData, photohandle, subsample, zoom);
    }
................................................................................
    
    *shift = 0;
    *bits = 0;
    
    /*
     * Find the lowest '1' bit in the mask.
     */

    for (i = 0; i < 32; ++i) {
        if (mask & 1 << i)
            break;
    }
    if (i < 32) {
        *shift = i;
        
        /*
        * Now find the next '0' bit and the width of the mask.
        */
 
        for ( ; i < 32; ++i) {
            if ((mask & 1 << i) == 0)
                break;
            else
                ++*bits;
        }
        
        /*
        * Limit to the top 8 bits if the mask was wider than 8.
        */

        if (*bits > 8) {
            *shift += *bits - 8;
            *bits = 8;
        }
    }
}

................................................................................
 * Side effects:
 *      Canvas contents from within the -scrollregion or widget size are rendered
 *      into the Photo. Any errors are left in the result.
 *
 *----------------------------------------------------------------------
 */

#define OVERDRAW_PIXELS 32        /* How much larger we make the pixmap
                                   * that the canvas objects are drawn into */

/* From stackoverflow.com/questions/2100331/c-macro-definition-to-determine-big-endian-or-little-endian-machine */
#define IS_BIG_ENDIAN (*(unsigned short *)"\0\xff" < 0x100)

#define BYTE_SWAP16(n) ((((unsigned short)n)>>8) | (((unsigned short)n)<<8))
#define BYTE_SWAP32(n) (((n>>24)&0x000000FF) | ((n<<8)&0x00FF0000) | ((n>>8)&0x0000FF00) | ((n<<24)&0xFF000000))

static int
DrawCanvas(
    Tcl_Interp *interp,           /* As passed to the widget command, and we will leave errors here */
    ClientData clientData,
................................................................................
    Visual *visualPtr;
    GC xgc = 0;
    XGCValues xgcValues;
    int canvasX1, canvasY1, canvasX2, canvasY2, cWidth, cHeight,
        pixmapX1, pixmapY1, pixmapX2, pixmapY2, pmWidth, pmHeight,
        bitsPerPixel, bytesPerPixel, x, y, result = TCL_OK,
        rshift, gshift, bshift, rbits, gbits, bbits;

#ifdef DEBUG_DRAWCANVAS
    char buffer[128];
#endif

    if ((tkwin = canvasPtr->tkwin) == NULL) {
        Tcl_AppendResult(interp, "canvas tkwin is NULL!", NULL);
        result = TCL_ERROR;
        goto done;
    }

    /*
     * If this canvas is unmapped, then we won't have a window id, so we will
     * try the ancestors of the canvas until we find a window that has a
     * valid window id. The Tk_GetPixmap() call requires a valid window id.
     */

    do {

        if ((displayPtr = Tk_Display(tkwin)) == NULL) {
            Tcl_AppendResult(interp, "canvas (or parent) display is NULL!", NULL);
            result = TCL_ERROR;
            goto done;
        }
................................................................................
    }

    /*
    * Scan through the item list, registering the bounding box for all items
    * that didn't do that for the final coordinates yet. This can be
    * determined by the FORCE_REDRAW flag.
    */

    for (itemPtr = canvasPtr -> firstItemPtr; itemPtr != NULL; 
            itemPtr = itemPtr -> nextPtr) {
        if (itemPtr -> redraw_flags & FORCE_REDRAW) {
            itemPtr -> redraw_flags &= ~FORCE_REDRAW;
            EventuallyRedrawItem(canvasPtr, itemPtr);
            itemPtr -> redraw_flags &= ~FORCE_REDRAW;
        }
    }

    /*
     * The DisplayCanvas() function works out the region that needs redrawing,
     * but we don't do this. We grab the whole scrollregion or canvas window
     * area. If we have a defined -scrollregion we use that as the drawing
     * region, otherwise use the canvas window height and width with an origin
     * of 0,0.
     */
    if (canvasPtr->scrollX1 != 0 || canvasPtr->scrollY1 != 0 ||
            canvasPtr->scrollX2 != 0 || canvasPtr->scrollY2 != 0) {

        canvasX1 = canvasPtr->scrollX1;
        canvasY1 = canvasPtr->scrollY1;
        canvasX2 = canvasPtr->scrollX2;
        canvasY2 = canvasPtr->scrollY2;
        cWidth = canvasX2 - canvasX1 + 1;
        cHeight = canvasY2 - canvasY1 + 1;
................................................................................
        canvasX1 = 0;
        canvasY1 = 0;
        canvasX2 = canvasX1 + cWidth - 1;
        canvasY2 = canvasY1 + cHeight - 1;
    }
    
    /*
     * Allocate a pixmap to draw into. We add OVERDRAW_PIXELS in the same way
     * that DisplayCanvas() does to avoid problems on some systems when objects
     * are being drawn too close to the edge.
     */

    pixmapX1 = canvasX1 - OVERDRAW_PIXELS;
    pixmapY1 = canvasY1 - OVERDRAW_PIXELS;
    pixmapX2 = canvasX2 + OVERDRAW_PIXELS;
    pixmapY2 = canvasY2 + OVERDRAW_PIXELS;
    pmWidth = pixmapX2 - pixmapX1 + 1;
    pmHeight = pixmapY2 - pixmapY1 + 1;
    if ((pixmap = Tk_GetPixmap(displayPtr, Tk_WindowId(tkwin), pmWidth, pmHeight,
            bitsPerPixel)) == 0) {
        Tcl_AppendResult(interp, "failed to create drawing Pixmap", NULL);
        result = TCL_ERROR;
        goto done;
    }

    /*
     * Before we can draw the canvas objects into the pixmap it's background
     * should be filled with canvas background colour.
     */

    xgcValues.function = GXcopy;
    xgcValues.foreground = Tk_3DBorderColor(canvasPtr->bgBorder)->pixel;
    xgc = XCreateGC(displayPtr, pixmap, GCFunction|GCForeground, &xgcValues);
    XFillRectangle(displayPtr,pixmap,xgc,0,0,pmWidth,pmHeight);

    /*
     * Draw all the cavas items into the pixmap
     */

    canvasPtr->drawableXOrigin = pixmapX1;
    canvasPtr->drawableYOrigin = pixmapY1;
    for (itemPtr = canvasPtr->firstItemPtr; itemPtr != NULL;
            itemPtr = itemPtr->nextPtr) {
        if ((itemPtr->x1 >= pixmapX2) || (itemPtr->y1 >= pixmapY2) ||
                (itemPtr->x2 < pixmapX1) || (itemPtr->y2 < pixmapY1)) {
            if (!AlwaysRedraw(itemPtr)) {
                continue;
            }
        }
        if (itemPtr->state == TK_STATE_HIDDEN || 
                (itemPtr->state == TK_STATE_NULL && canvasPtr->canvas_state
                == TK_STATE_HIDDEN)) {
            continue;
        }
        ItemDisplay(canvasPtr, itemPtr, pixmap, pixmapX1, pixmapY1, pmWidth,
                pmHeight);
    }
    
    /*
     * Copy the Pixmap into an ZPixmap format XImage so we can copy it across
     * to the photo image. This seems to be the only way to get Pixmap image
     * data out of an image. Note we have to account for the OVERDRAW_PIXELS
     * border width.
     */

    if ((ximagePtr = XGetImage(displayPtr, pixmap, -pixmapX1, -pixmapY1, cWidth,
            cHeight, AllPlanes, ZPixmap)) == NULL) {
        Tcl_AppendResult(interp, "failed to copy Pixmap to XImage", NULL);
        result = TCL_ERROR;
        goto done;
    }
    
#ifdef DEBUG_DRAWCANVAS
    Tcl_AppendResult(interp, "ximagePtr {", NULL);
    sprintf(buffer,"%d",ximagePtr->width);   Tcl_AppendResult(interp, " width ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->height);  Tcl_AppendResult(interp, " height ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->xoffset); Tcl_AppendResult(interp, " xoffset ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->format);  Tcl_AppendResult(interp, " format ", buffer, NULL);
                                             Tcl_AppendResult(interp, " ximagePtr->data", NULL);
    if (ximagePtr->data != NULL) {
	int ix, iy;

        Tcl_AppendResult(interp, " {", NULL);
	for (iy = 0; iy < ximagePtr->height; ++ iy) {
	    Tcl_AppendResult(interp, " {", NULL);
	    for (ix = 0; ix < ximagePtr->bytes_per_line; ++ ix) {
	        if (ix > 0) {
                    if (ix % 4 == 0)
                        Tcl_AppendResult(interp, "-", NULL);
                    else
                        Tcl_AppendResult(interp, " ", NULL);
                }
	        sprintf(buffer,"%2.2x",ximagePtr->data[ximagePtr->bytes_per_line * iy + ix]&0xFF);
	        Tcl_AppendResult(interp, buffer, NULL);
	    }
	    Tcl_AppendResult(interp, " }", NULL);
	}
	Tcl_AppendResult(interp, " }", NULL);
    } else
	sprintf(buffer," NULL");
    sprintf(buffer,"%d",ximagePtr->byte_order);       Tcl_AppendResult(interp, " byte_order ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bitmap_unit);      Tcl_AppendResult(interp, " bitmap_unit ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bitmap_bit_order); Tcl_AppendResult(interp, " bitmap_bit_order ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bitmap_pad);       Tcl_AppendResult(interp, " bitmap_pad ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->depth);            Tcl_AppendResult(interp, " depth ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bytes_per_line);   Tcl_AppendResult(interp, " bytes_per_line ", buffer, NULL);
    sprintf(buffer,"%d",ximagePtr->bits_per_pixel);   Tcl_AppendResult(interp, " bits_per_pixel ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",ximagePtr->red_mask);   Tcl_AppendResult(interp, " red_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",ximagePtr->green_mask); Tcl_AppendResult(interp, " green_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",ximagePtr->blue_mask);  Tcl_AppendResult(interp, " blue_mask ", buffer, NULL);
    Tcl_AppendResult(interp, " }", NULL);
    
    Tcl_AppendResult(interp, "\nvisualPtr {", NULL);
    sprintf(buffer,"0x%8.8lx",visualPtr->red_mask);   Tcl_AppendResult(interp, " red_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",visualPtr->green_mask); Tcl_AppendResult(interp, " green_mask ", buffer, NULL);
    sprintf(buffer,"0x%8.8lx",visualPtr->blue_mask);  Tcl_AppendResult(interp, " blue_mask ", buffer, NULL);
    Tcl_AppendResult(interp, " }", NULL);
    
#endif

    /*
     * Fill in the PhotoImageBlock structure abd allocate a block of memory
     * for the converted image data. Note we allocate an alpha channel even
     * though we don't use one, because this layout helps Tk_PhotoPutBlock()
     * use memcpy() instead of the slow pixel or line copy.
     */

    blockPtr.width = cWidth;
    blockPtr.height = cHeight;
    blockPtr.pixelSize = 4;
    blockPtr.pitch = blockPtr.pixelSize * blockPtr.width;
    blockPtr.offset[0] = 0;
    blockPtr.offset[1] = 1;
    blockPtr.offset[2] = 2;
    blockPtr.offset[3] = 3;
    blockPtr.pixelPtr = ckalloc(blockPtr.pixelSize * blockPtr.height * blockPtr.width);

    /*
     * Now convert the image data pixel by pixel from XImage to 32bit RGBA
     * format suitable for Tk_PhotoPutBlock().
     */

    DecomposeMaskToShiftAndBits(visualPtr->red_mask,&rshift,&rbits);
    DecomposeMaskToShiftAndBits(visualPtr->green_mask,&gshift,&gbits);
    DecomposeMaskToShiftAndBits(visualPtr->blue_mask,&bshift,&bbits);

#ifdef DEBUG_DRAWCANVAS
    sprintf(buffer,"%d",rshift); Tcl_AppendResult(interp, "\nbits { rshift ", buffer, NULL);
    sprintf(buffer,"%d",gshift); Tcl_AppendResult(interp, " gshift ", buffer, NULL);
    sprintf(buffer,"%d",bshift); Tcl_AppendResult(interp, " bshift ", buffer, NULL);
    sprintf(buffer,"%d",rbits);  Tcl_AppendResult(interp, " rbits ", buffer, NULL);
    sprintf(buffer,"%d",gbits);  Tcl_AppendResult(interp, " gbits ", buffer, NULL);
    sprintf(buffer,"%d",bbits);  Tcl_AppendResult(interp, " bbits ", buffer, " }", NULL);
    Tcl_AppendResult(interp, "\nConverted_image {", NULL);
#endif

    /* Ok, had to use ximagePtr->bits_per_pixel here and in the switch (...)
     * below to get this to work on Windows. X11 correctly sets the bitmap
     *_pad and bitmap_unit fields to 32, but on Windows they are 0 and 8
     * respectively!
     */

    bytesPerPixel = ximagePtr->bits_per_pixel/8;
    for (y = 0; y < blockPtr.height; ++y) {

#ifdef DEBUG_DRAWCANVAS
        Tcl_AppendResult(interp, " {", NULL);
#endif

        for(x = 0; x < blockPtr.width; ++x) {
            unsigned long pixel;

            switch (ximagePtr->bits_per_pixel) {

                /*
                 * Get an 8 bit pixel from the XImage.
                 */

                case 8 :
                    pixel = *((unsigned char *)(ximagePtr->data + bytesPerPixel * x
                            + ximagePtr->bytes_per_line * y));
                    break;

                /*
                 * Get a 16 bit pixel from the XImage, and correct the
                 * byte order as necessary.
                 */

                case 16 :
                    pixel = *((unsigned short *)(ximagePtr->data + bytesPerPixel * x
                            + ximagePtr->bytes_per_line * y));
                    if ((IS_BIG_ENDIAN && ximagePtr->byte_order == LSBFirst)
                            || (!IS_BIG_ENDIAN && ximagePtr->byte_order == MSBFirst))
                        pixel = BYTE_SWAP16(pixel);
                    break;

                /*
                 * Grab a 32 bit pixel from the XImage, and correct the
                 * byte order as necessary.
                 */

                case 32 :
                    pixel = *((unsigned long *)(ximagePtr->data + bytesPerPixel * x
                            + ximagePtr->bytes_per_line * y));
                    if ((IS_BIG_ENDIAN && ximagePtr->byte_order == LSBFirst)
                            || (!IS_BIG_ENDIAN && ximagePtr->byte_order == MSBFirst))
                        pixel = BYTE_SWAP32(pixel);
                    break;
            }

            /*
             * We have a pixel with the correct byte order, so pull out the
             * colours and place them in the photo block. Perhaps we could
             * just not bother with the alpha byte because we are using
             * TK_PHOTO_COMPOSITE_SET later?
             * ***Windows: We have to swap the red and blue values. The
             * XImage storage is B - G - R - A which becomes a 32bit ARGB
             * quad. However the visual mask is a 32bit ABGR quad. And
             * Tk_PhotoPutBlock() wants R-G-B-A which is a 32bit ABGR quad.
             * If the visual mask was correct there would be no need to
             * swap anything here.
             */

#ifdef _WIN32
#define   R_OFFSET 2
#define   B_OFFSET 0
#else
#define   R_OFFSET 0
#define   B_OFFSET 2
#endif
            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x + R_OFFSET] =
                    (unsigned char)((pixel & visualPtr->red_mask) >> rshift);
            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x +1] =
                    (unsigned char)((pixel & visualPtr->green_mask) >> gshift);
            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x + B_OFFSET] =
                    (unsigned char)((pixel & visualPtr->blue_mask) >> bshift);
            blockPtr.pixelPtr[blockPtr.pitch * y + blockPtr.pixelSize * x +3] = 0xFF;

#ifdef DEBUG_DRAWCANVAS
            {
		int ix;
                if (x > 0)
                    Tcl_AppendResult(interp, "-", NULL);
	        for (ix = 0; ix < 4; ++ix) {
                    if (ix > 0)
                        Tcl_AppendResult(interp, " ", NULL);
		    sprintf(buffer,"%2.2x",blockPtr.pixelPtr[blockPtr.pitch * y
                            + blockPtr.pixelSize * x + ix]&0xFF);
                    Tcl_AppendResult(interp, buffer, NULL);
                }
            }
#endif

        }

#ifdef DEBUG_DRAWCANVAS
        Tcl_AppendResult(interp, " }", NULL);
#endif

    }

#ifdef DEBUG_DRAWCANVAS
    Tcl_AppendResult(interp, " }", NULL);
#endif

    /*
     * Now put the copied pixmap into the photo.
     * If either zoom or subsample are not 1, we use the zoom function.
     */

    if (subsample != 1 || zoom != 1) {
        if ((result = Tk_PhotoPutZoomedBlock(interp, photohandle, &blockPtr,
                0, 0, cWidth * zoom / subsample, cHeight * zoom / subsample,
                zoom, zoom, subsample, subsample, TK_PHOTO_COMPOSITE_SET))
                != TCL_OK) {
            goto done;
        }
    } else {
        if ((result = Tk_PhotoPutBlock(interp, photohandle, &blockPtr, 0, 0,
            cWidth, cHeight, TK_PHOTO_COMPOSITE_SET)) != TCL_OK) {
            goto done;
        }
    }

    /*
     * Clean up anything we have allocated and exit.
     */

done:
    if (blockPtr.pixelPtr)
        ckfree(blockPtr.pixelPtr);
    if (pixmap)
        Tk_FreePixmap(Tk_Display(tkwin), pixmap);
    if (ximagePtr)
        XDestroyImage(ximagePtr);