Developer CD Series 1996 …ember: Reference Library/Dev.CD Dec 96 RL/Dev.CD Dec 96 RL.toast/Technical Documentation/develop/develop Issue 21/develop Issue 21 code/OpenDoc Graphics Recipes

Text File | 1995-01-16 | 13.0 KB | 402 lines | [TEXT/ttxt]

// Listing 1. MyPart::Draw, simplest case
void MyPart::Draw(Environment* ev, ODFacet* facet, ODShape* invalShape)
{
    // Set up graphics port.
    GrafPtr port = facet->GetCanvas(ev)->GetQDPort(ev);
    SetPort(port);

    // Set up graphics port offset for drawing content.
    ODTransform* localToGlobal = facet->GetContentTransform(ev, kODNULL);
    ODPoint offset(0,0);
    offset = localToGlobal->TransformPoint(ev, &offset);
    SetOrigin(-offset.IntX(), -offset.IntY());
    localToGlobal->Release(ev);

    // Set up graphics port clip; save old clip.
    RgnHandle saveClip = NewRgn();
    GetClip(saveClip);
    ODShape* clipShape = facet->GetAggregateClipShape(ev, kODNULL);
    RgnHandle clip = clipShape->GetQDRegion(ev);
    SetClip(clip);
    clipShape->Release(ev);

    // And draw (insert your drawing code here).
    // Remember to respect the scaling and rotation information
    // in your content transform, if possible. If you can't do this,
    // it's graceful to at least try to draw as best you can, rather
    // than simply signaling an error.
    ...

    // Clean up.
    SetClip(saveClip);
    DisposeRgn(saveClip);
    SetOrigin(0,0);
}

// Listing 2. MyPart::Draw, with scrolling
void MyPart::Draw(Environment* ev, ODFacet* facet, ODShape* invalShape)
{
    Point        spclOffset = {0,0};
    Point        contentOffset = {0,0};

    // Set up graphics port.
    GrafPtr port = facet->GetCanvas(ev)->GetQDPort(ev);
    SetPort(port);

    // Set up graphics port offsets for controls.
    ODTransform* localToGlobal = facet->GetFrameTransform(ev, kODNULL);
    ODPoint tempOffset1(0,0);
    tempOffset1 = localToGlobal->TransformPoint(ev, &tempOffset1);
    SetOrigin(-tempOffset1.IntX(), -tempOffset1.IntY());

    // Set up special offset for later efficient reset of clipping region.
    spclOffset = localToGlobal->GetQDOffset(ev);
    ODTransform* contentTransform = facet->GetContentTransform(ev,
            kODNULL);
    contentOffset = contentTransform->GetQDOffset(ev);
    spclOffset.v -= contentOffset.v; spclOffset.h -= contentOffset.h;
    localToGlobal->Release(ev);

    // Set up graphics port clipping.
    RgnHandle saveClip = NewRgn();
    GetClip(saveClip);
    ODShape* clipShape = facet->GetAggregateClipShape(ev, kODNULL);
    RgnHandle clip = clipShape->GetQDRegion(ev);
    SetClip(clip);

    // Draw your controls (such as scroll bars) here, using the standard
    // Toolbox calls. Remember to respect the scaling and rotation
    // information in your transform, or at least try to draw as best
    // you can, rather than simply signaling an error.
    ...

    // Set up graphics port for drawing content.
    ODPoint tempOffset2(0,0);
    tempOffset2 = contentTransform->TransformPoint(ev, &tempOffset2);
    SetOrigin(-tempOffset2.IntX(), -tempOffset2.IntY());

    // Use the special offset we set up earlier to keep the clip in the
    // right place relative to the origin. Remember to remove the scroll
    // bar area from the clipping region.
    OffsetRgn(clip, spclOffset.h, spclOffset.v);
    SetClip(clip);

    // And draw (insert your drawing code here).
    // Remember to respect the scaling and rotation information
    // in your content transform if possible, as mentioned above.
    ...

    // Clean up.
    SetClip(saveClip);
    DisposeRgn(saveClip);
    contentTransform->Release(ev);
    clipShape->Release(ev);
    SetOrigin(0, 0);
}

// Listing 3. Handling the scrolling
ODBoolean MyPart::HandleMouseDownScrollBar(Environment* ev, Point mouse,
        ODFrame* frame)
{
    ODSShort partcode = TrackControl(fScrollBar, mouse, kODNULL);
    Point transPt;
    ODSShort setting = GetControlValue(fScrollBar);

    if (partcode) {
        // Deal with the scroll bar and choose the scroll distance.
        switch (partcode) {
            case inUpButton:
                setting--;
                break;
            case inDownButton:
                setting++;
                break;
            case inPageUp:
                if ((setting - kPBPageSize) < 0) setting = 0;
                else setting -= kPBPageSize;
                break;
            case inPageDown:
                ODSShort max = GetControlMaximum(fScrollBar);
                if ((setting + kPBPageSize) > max) setting = max;
                else setting += kPBPageSize;
                break;
            default:
                break;
        }

        SetControlValue(fScrollBar, setting);
        SetPt(&transPt, 0, (0-setting));        // This is a vertical
                                                        // scroll bar.

        // Set up the transform.
        ODTransform* newIntTrans = frame->CreateTransform(ev);
        newIntTrans->SetQDOffset(ev, &transPt);
        frame->ChangeInternalTransform(ev, newIntTrans, kODNULL);
        newIntTrans->Release(ev);

        // Here's some simplified code for invalidating any embedded
        // facets that have been moved. This is a "saturation bombing"
        // approach rather than the tuned code of a real application,
        // but it gets the basic idea across. Typically, we do a
        // ScrollRect followed by invalidation of the revealed area.
        // Here we simply invalidate everything.
        frame->Invalidate(ev, kODNULL, kODNULL);
        return kODTrue;
    }
    return kODFalse;
}


// Listing 4. A 4x scaling operation
void MyPart::ZoomContents4X(Environment* ev, ODFrame* frame)
{
    ODPoint        frameScale(4, 4);

    // Apply the zoom transformation.
    ODTransform* intTrans = frame->GetInternalTransform(ev, kODNULL);
    intTrans->ScaleBy(ev, &frameScale);
    intTrans->Release(ev);

    // Invalidate the frame for redrawing.
    frame->Invalidate(ev, kODNULL, kODNULL);
}

// Listing 5. Making an embedded part visible
void MyPart::EmbedPartFromSU(Environment* ev, ODStorageUnit* newSU,
        ODFacet* myFacet)
{
    ODPart* newPart = newSU->GetDraft(ev)->GetPart(ev, newPartID);
    ODRect rect(0, 0, kPBDefaultFrameSize, kPBDefaultFrameSize);
    ODShape* newFrameShape = myFacet->CreateShape(ev);
    newFrameShape->SetRectangle(ev, &rect);
    ODFrame* newFrame = newSU->GetDraft(ev)->CreateFrame(ev,
            kODNULL,                         // Use the default frame type.
            myFacet->GetFrame(ev),        // Containing frame is my frame.
            newFrameShape,                    // Use the frame shape we set up.
            (ODCanvas*)kODNULL,            // No special canvas.
            newPart,                            // The part in the frame.
            fSession->Tokenize(ev, kODViewAsFrame),    // View as a frame.
            kODNullTypeToken,                // Undefined presentation.
            kODFalse,                        // Not a root frame.
            kODFalse);                        // Not overlaid.
    newSU->Release(ev);
    // Set up a clip shape, same as frame shape.
    ODShape* frameShape = newFrame->GetFrameShape(ev, kODNULL);
    ODShape* newClipShape = frameShape->Copy(ev);
    Point offset = {100,100};
    ODTransform* newExternalXForm = myFacet->CreateTransform(ev);
    newExternalXForm->SetQDOffset(ev, &offset);
    ODFacet* newFacet = myFacet->CreateEmbeddedFacet(ev,
            newFrame,                 // Of this frame.
            newClipShape,             // With this clip shape.
            newExternalXForm,        // At this location/scale/rotation.
            kODNULL,                    // No special canvas.
            kODNULL,                    // No special bias canvas.
            kODNULL,                    // No sibling specified.
            kODFrameInFront);     // Put this facet at front.

    // At this point, we probably want to remember the new frame
    // and facet in some data structure.
    this->rememberFrame(newFrame, newFacet);

    // Invalidate facet so that it displays. We need to invalidate our
    // entire frame because the new facet may interact with other content
    // in various ways. This is the simplest correct method, although
    // optimizations may be reasonable in production code.
    myFacet->GetFrame(ev)->Invalidate(ev, kODNULL, kODNULL);

    // Clean up.
    newPart->Release(ev);
    newFrame->Release(ev);
    newFrameShape->Release(ev);
    newExternalXForm->Release(ev);
    newClipShape->Release(ev);
    frameShape->Release(ev);
}


// Listing 6. Altering the coordinate system scaling
void MyPart::ShiftCoordinateScaling(Environment* ev, ODFrame* frame)
{
    ODPoint        frameScale(72,72);

    // Set up the transform.
    ODTransform* existingTransform = frame->GetInternalTransform(ev,
        kODNULL);
    ODTransform* newIntTrans = existingTransform->Copy(ev);
    existingTransform->Release(ev);
    newIntTrans->ScaleDownBy(ev, &frameScale);

    // Apply the zoom transformation within myself.
    frame->ChangeInternalTransform(ev, newIntTrans, kODNULL);
    newIntTrans->Release(ev);

    // Now, be a good citizen and iterate over every facet of myself.
    ODFrameFacetIterator* facets = frame->CreateFacetIterator(ev);
    for (ODFacet* facet = facets->First(ev); facets->IsNotComplete(ev);
            facet = facets->Next(ev)) {
        // For each facet of myself, find every embedded facet.
        ODFacetIterator* embeddedFacets = facet->CreateFacetIterator(ev,
            kODTopDown, kODFrontToBack);
        for (ODFacet* embeddedFacet = embeddedFacets->First(ev);
                embeddedFacets->IsNotComplete(ev);
                embeddedFacet = embeddedFacets->Next(ev)) {
            // Alter the transform of each embedded facet.
            existingTransform = embeddedFacet->GetExternalTransform(ev,
                kODNULL);
            ODTransform* newExtTrans = existingTransform->Copy(ev);
            // Notice that we scale in the opposite direction in
            // each embedded frame.
            newExtTrans->ScaleBy(ev, &frameScale);
            embeddedFacet->ChangeGeometry(ev, kODNULL, newExtTrans,
                kODNULL);
            newExtTrans->Release(ev);
            existingTransform->Release(ev);
        }
        ODDeleteObject(embeddedFacets);
    }
    ODDeleteObject(facets);
}

// Listing 7. Setting clipping when printing to a PostScript device
#define kPostScriptBegin    190    // Picture comments for PostScript
#define kPostScriptEnd        191    // printing.
#define kPostScriptHandle    192

void ODBeginPostScriptClip(Environment* ev, ODShape *shape)
{
    ODPolygon poly = shape->CopyPolygon(ev);
    Handle clipHandle = NewEmptyHandle();

    AppendString("\pgrestore", clipHandle);    // Utility routine to append
    AppendString("\pnewpath", clipHandle);        // string to a handle.

    char buf[128];
    ODContour *cont = poly.FirstContour();

    for (long n=poly.GetNContours(); n>0; n--) {
        const ODPoint *v = cont->vertex;
        long m = cont->nVertices;
        if (m > 2) {
            sprintf(buf, "%.2f %.2f moveto", v->x/65536.0, v->y/65536.0);
            AppendBuf(buf, strlen(buf), clipHandle);    // Utility routine to
                                                // append string buffer to a handle.
            while (--m > 0) {
                v++;
                sprintf( buf, "%.2f %.2f lineto", v->x/65536.0,
                    v->y/65536.0);
                AppendBuf(buf, strlen(buf), clipHandle);
            }
        }
        AppendString("\pclosepath clip", clipHandle);
        cont = cont->NextContour();
    }

    // Set pic comment; then delete clipHandle.
    AppendString("\pgsave", clipHandle);
    PicComment(kPostScriptBegin, 0, kODNULL);
    PicComment(kPostScriptHandle, GetHandleSize(clipHandle), clipHandle);
    PicComment(kPostScriptEnd, 0, kODNULL);
    DisposeHandle(clipHandle);
}

void ODEndPostScriptClip( )
{
    Handle clipHandle = NewEmptyHandle();
    AppendString("\pgrestore", clipHandle);
    PicComment(kPostScriptBegin, 0, kODNULL);
    PicComment(kPostScriptHandle, GetHandleSize(clipHandle), clipHandle);
    PicComment(kPostScriptEnd, 0, kODNULL);
    DisposeHandle(clipHandle);
}

// Listing 8. Setup for basic printing
ODFacet* MyPart::BeginPrinting(Environment *ev, ODFrame* rootFrame,
        TPrPort* thePrPort, ODRect *pageRect)
{
    // Set up identity transform, get page rect, set up to clip to it.
    ODTransform* xtransform = rootFrame->CreateTransform(ev);
    ODShape* clipshape = rootFrame->CreateShape(ev);
    clipshape->SetRectangle(ev, pageRect);

    // Create a facet with the specific geometry we just set up.
    ODFacet* prFacet = fSession->GetWindowState(ev)->
            CreateFacet(ev, rootFrame, clipshape, xtransform, kODNULL,
            kODNULL);
    xtransform->Release(ev);
    clipshape->Release(ev);

    // Set up a canvas based on the print job's port.
    ODCanvas* prCanvas = prFacet->CreateCanvas(ev, kODQuickDraw,
            (GrafPtr)thePrPort, kODFalse, kODFalse);
    prCanvas->SetPlatformPrintJob(ev, kODQuickDraw, (GrafPtr)thePrPort);

    // Make it the canvas of the facet we created.
    prFacet->SetCanvas(ev, prCanvas);
    rootFrame->FacetAdded(ev, prFacet);

    // Return the facet to the main print routine.
    return prFacet;
}

// Listing 9. Printing a page
void MyPart::PrintPage(Environment *ev, ODFacet* prFacet, ODUShort page,
    ODRect *pageRect)
{
    // Get some basic printing geometry.
    ODRect    bbox;
    Rect        frect, qdPRect;

    ODShape* frameShape = prFacet->GetFrame(ev)->
            GetFrameShape(ev, kODNULL);
    frameShape->GetBoundingBox(ev, &bbox);
    bbox.AsQDRect(frect);
    frameShape->Release(ev);
    Point pt = {0,0};
    ODUShort locator = page-1;

    // Pick an appropriate offset, based on page number.
    pageRect->AsQDRect(qdPRect);
    while (locator) {
        pt.v += (qdPRect.bottom+1);
        locator--;
        if (PtInRect(pt, &frect))
            continue;
        else {
            pt.v = 0; pt.h += (qdPRect.right+1);
        }
    }

    // Make a transform for that offset.
    ODTransform* xtransform = prFacet->CreateTransform(ev);
    xtransform->SetQDOffset(ev, &pt);

    // Create a clip shape for the page, based on the transform.
    ODShape* clipshape = prFacet->CreateShape(ev);
    clipshape->SetRectangle(ev, pageRect);
    ODShape* invalshape = clipshape->Copy(ev);
    clipshape->Transform(ev, xtransform);
    xtransform->Invert(ev);

    // Change the geometry of the printing facet.
    prFacet->ChangeGeometry(ev, clipshape, xtransform, kODNULL);

    // Draw everything on the page. OpenDoc will call the Draw method
    // on every part visible on the page.
    prFacet->Update(ev, invalshape, kODNULL);

    // Clean up.
    clipshape->Release(ev);
    invalshape->Release(ev);
    xtransform->Release(ev);
}

// Listing 10. Cleanup after printing
void MyPart::EndPrinting(Environment *ev, ODFacet* prFacet)
{
    // Find the printing canvas and facet; delete them.
    ODCanvas* prCanvas = prFacet->GetCanvas(ev);
    prFacet->GetFrame(ev)->FacetRemoved(ev, prFacet);
    delete prCanvas;
    delete prFacet;
}