examples/Graphics/GraphicsShell/Draw.cpp

// Copyright (c) 2000-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

#include "GraphicsControl.h"

#include <coemain.h>

// Text printed to the console in UpdateModeL()
_LIT(KTxtUpdateModelCase0,"point in center of screen");
_LIT(KTxtUpdateModelCase1,"bolder point in center of screen");
_LIT(KTxtUpdateModelCase2,"really bold point in center of screen");
_LIT(KTxtUpdateModelCase3,"a line");
_LIT(KTxtUpdateModelCase4,"a thicker line");
_LIT(KTxtUpdateModelCase5,"really thick - note round ends and clipping");
_LIT(KTxtUpdateModelCase6,"dotted line");
_LIT(KTxtUpdateModelCase7,"dot-dash line");
_LIT(KTxtUpdateModelCase8,"triangle using relative drawing");
_LIT(KTxtUpdateModelCase9,"thick triangle - note rounded corners");
_LIT(KTxtUpdateModelCase10,"dotted triangle - note pattern continuation");
_LIT(KTxtUpdateModelCase11,"centered ellipse");
_LIT(KTxtUpdateModelCase12,"arc - part of ellipse");
_LIT(KTxtUpdateModelCase13,"arc - other part - see also construction elements");
_LIT(KTxtUpdateModelCase14,"pie slices");
_LIT(KTxtUpdateModelCase15,"centered rectangle with rounded corners");
_LIT(KTxtUpdateModelCase16,"rounded rectangle showing corner ellipse");
_LIT(KTxtUpdateModelCase17,"polyline");
_LIT(KTxtUpdateModelCase18,"polygon with winding-fill rule");
_LIT(KTxtUpdateModelCase19,"polygon using alternate-fill rule");
_LIT(KTxtUpdateModelCase20,"copying using CopyRect()");
_LIT(KTxtUpdateModelCase21,"left-justified boxed text");
_LIT(KTxtUpdateModelCase22,"centered boxed text");
_LIT(KTxtUpdateModelCase23,"right-justified offset text");
_LIT(KTxtUpdateModelCase24,"cross-hatched box");
_LIT(KTxtUpdateModelCase25,"teeny preview font!");
_LIT(KTxtUpdateModelDefault,"overran!");

static CArrayFix<TPoint>* CreatePointsArrayL();

void CDrawControl::UpdateModelL()
        {
        switch (Phase())
                {
                case 0:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase0);
                        break;
                case 1:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase1);
                        break;
                case 2:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase2);
                        break;
                case 3:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase3);
                        break;
                case 4:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase4);
                        break;
                case 5:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase5);
                        break;
                case 6:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase6);
                        break;
                case 7:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase7);
                        break;
                case 8:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase8);
                        break;
                case 9:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase9);
                        break;
                case 10:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase10);
                        break;
                case 11:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase11);
                        break;
                case 12:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase12);
                        break;
                case 13:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase13);
                        break;
                case 14:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase14);
                        break;
                case 15:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase15);
                        break;
                case 16:
                        {
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase16);
                        }
                        break;
                case 17:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase17);
                        break;
                case 18:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase18);
                        break;
                case 19:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase19);
                        break;
                case 20:
                        {
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase20);
                        }
                        break;
                case 21:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase21);
                        break;
                case 22:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase22);
                        break;
                case 23:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase23);
                        break;
                case 24:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase24);
                        break;
                case 25:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelCase25);
                        break;
                default:
                        iGraphObserver->NotifyStatus(KTxtUpdateModelDefault);
                        break;
                }
        }


// Text printed to the console in UpdateModeL()
_LIT(KTxtDrawCase21,"White text left justified in dark gray box");
_LIT(KTxtDrawCase22,"White text centered in black box");
_LIT(KTxtDrawCase23,"Dark gray text right justified in lite gray box");
_LIT(KTxtDrawCase25,"This text overwrites the cleared area");

        
void CDrawControl::Draw(const TRect& /* aRect */) const
        {
        // put the next line back in to see the individual drawing actions
        // (iCoeEnv->WsSession()).SetAutoFlush(ETrue);
        // draw surrounding rectangle
        CWindowGc& gc=SystemGc(); // graphics context we draw to
        gc.UseFont(iMessageFont); // use the system message font
        gc.Clear();
        SystemGc().DrawRect(Rect()); // surrounding rectangle to draw into
        TRect rect=Rect(); // a centered rectangle of the default size
        TRect ellipseRect=Rect(); // for arcs and ellipse
        ellipseRect.Shrink(10,10); // set size so inside the border rectangle
        TRect box=Rect(); // a smaller centered rectangle, for text in a box
        box.Shrink(10,10); // set size of text box
        TRect tinyBox=Rect(); // a tiny box to clear
        tinyBox.Shrink(220,90); // set size of tiny box to clear
        TInt offset=0; // offset, for text in a box
        TPoint screenCenterPoint=rect.Center(); // the center of the screen 
        // set up a pair of construction points for arc and pie slice drawing
        // set up the size for half a screen (divided vertically)
        TPoint constructionPoint1(15,15); // outside the construction ellipse
        TPoint constructionPoint2(200,150); // inside the construction ellipse
        // set up a pair of points for drawing diagonal lines
        TPoint startPoint(50,50);
        TPoint endPoint(590,190);
        // set up an array of points for drawing a polyline and a polygon etc
        // will be used relative to top left of rectangle
        CArrayFix<TPoint>* mypoints=NULL;
        TRAPD(err,mypoints = CreatePointsArrayL());
        if(err)
                {
                return;
                }
        // set up a black, a dark gray, a lite gray and a white RGB color
        TRgb black(0,0,0);
        TRgb darkGray(85,85,85);
        TRgb liteGray(170,170,170);
        TRgb white(255,255,255); // appears as blank screen gray-green color
        // Set up a "bold" size for the pen tip to (default is 1,1)
        TSize penSizeBold(3,3);
        // Set up a "fat" size for the pen tip
        TSize penSizeFat(30,30);
        // decide what to do, and do it
        switch (Phase())
                {
                case 0:
                        // draw a single pixel point in the center of the screen
                        // it is so small that some text is needed to explain the screen...
                        gc.Plot(screenCenterPoint);
                        break;
                case 1:
                        // draw a "bold" point 3 pixels across
                        gc.SetPenSize(penSizeBold);
                        gc.Plot(screenCenterPoint);
                        break;
                case 2:
                        // draw a "fat" point (circular blob),
                        // illustrating the effect of a very wide pen
                        gc.SetPenSize(penSizeFat);
                        gc.Plot(screenCenterPoint);
                        break;
                case 3:
                        // draw a thin line fromtop left to bottom right
                        gc.DrawLine(startPoint,endPoint);
                        break;
                case 4:
                        // draw a "bold" line fromtop left to bottom right
                        gc.SetPenSize(penSizeBold);
                        gc.DrawLine(startPoint,endPoint);
                        break;
                case 5:
                        // draw a rather wide line from top left to bottom right,
                        // illustrating rounded ends and their clipping
                        gc.SetPenSize(penSizeFat);
                        gc.DrawLine(startPoint,endPoint);
                        break;
                case 6:
                        // draw a dotted line from top left to bottom right
                        gc.SetPenStyle(CGraphicsContext::EDottedPen);
                        gc.DrawLine(startPoint,endPoint);
                        break;
                case 7:
                        // draw a dot-dash line from top left to bottom right
                        gc.SetPenStyle(CGraphicsContext::EDotDashPen);
                        gc.DrawLine(startPoint,endPoint);
                        break;
                case 8:
                        // draw a triangle by relative drawing
                        gc.MoveTo(TPoint(300,50)); // drawing position (300,50)
                        gc.DrawLineBy(TPoint(205,100)); // drawing position (505,150)
                        gc.DrawLineBy(TPoint(-410,0)); // drawing position (95,150)
                        gc.DrawLineBy(TPoint(205,-100)); // drawing position (300,50)
                        break;
                case 9:
                        // draw a triangle, by relative drawing
                        // illustrating rounded ends at corners when using very wide lines
                        gc.SetPenSize(penSizeFat);
                        gc.MoveTo(TPoint(300,50)); // drawing position (300,50)
                        gc.DrawLineBy(TPoint(205,100)); // drawing position (505,150)
                        gc.DrawLineBy(TPoint(-410,0)); // drawing position (95,150)
                        gc.DrawLineBy(TPoint(205,-100)); // drawing position (300,50)
                        break;
                case 10:
                        // draw a triangle by sequential drawing between specified points,
                        // using dot-dash line style, illustrating line pattern continuation 
                        gc.SetPenStyle(CGraphicsContext::EDotDashPen);
                        gc.MoveTo(TPoint(300,50)); // drawing position (300,50)
                        gc.DrawLineTo(TPoint(505,150)); // drawing position (505,150)
                        gc.DrawLineTo(TPoint(95,150)); // drawing position (95,150)
                        gc.DrawLineTo(TPoint(300,50)); // drawing position (300,50)
                        break;
                case 11:
                        // draw an ellipse centered in the rectangle
                        gc.DrawEllipse(ellipseRect);
                        break;
                case 12:
                        // draw an arc centered in the rectangle
                        gc.DrawArc(ellipseRect,constructionPoint1,constructionPoint2);
                        // gc.Clear();
                        break;
                case 13:
                        // draw an arc centered in the rectangle that is the other
                        // portion of the ellipse (arguments reversed)
                        gc.DrawArc(ellipseRect,constructionPoint2,constructionPoint1);
                        // draw construction lines and points
                        gc.SetPenStyle(CGraphicsContext::EDottedPen);
                        gc.MoveTo(constructionPoint1);
                        gc.DrawLineTo(screenCenterPoint);
                        gc.DrawLineTo(constructionPoint2);
                        gc.SetPenSize(penSizeBold);
                        gc.Plot(constructionPoint1);
                        gc.Plot(constructionPoint2);
                        gc.Plot(screenCenterPoint);
                        break;
                case 14:
                        // draw a pie slice centered in the rectangle
                        gc.SetBrushStyle(CGraphicsContext::ESolidBrush);
                        gc.SetBrushColor(white);
                        gc.DrawPie(ellipseRect,constructionPoint1,constructionPoint2);
                        // draw the other portion of the elliptical disc
                        gc.SetBrushStyle(CGraphicsContext::EVerticalHatchBrush);
                        gc.DrawPie(ellipseRect,constructionPoint2,constructionPoint1);
                        break;
                case 15:
                        {
                        // draw a rectangle with rounded corners, centered in the rectangle
                        TSize cornerSize(20,20); // size of a rounded corner
                        gc.DrawRoundRect(box,cornerSize); // same rect as text box
                        }
                        break;
                case 16:
                        {
                        // draw a rectangle with rounded corners,
                        //centered in the rectangle, showing a corner ellipse
                        TSize cornerSize(20,20); // size of a rounded corner
                        // rect for corner ellipse is twice the corner size
                        TSize cornerEllipseSize(cornerSize.iHeight*2,cornerSize.iWidth*2);
                        TRect cornerRectTl(box.iTl,cornerEllipseSize);
                        gc.DrawRoundRect(box,cornerSize);
                        gc.SetPenStyle(CGraphicsContext::EDottedPen);
                        gc.DrawEllipse(cornerRectTl); // corner construction ellipse
                        }
                        break;
                case 17:
                        // draw a polyline
                        gc.DrawPolyLine(mypoints);
                        break;
                case 18:
                        // draw self-crossing polygon using the winding fill rule
                        gc.SetBrushStyle(CGraphicsContext::ESquareCrossHatchBrush);
                        gc.SetBrushColor(black);
                        gc.DrawPolygon(mypoints,CGraphicsContext::EWinding);
                        break;
                case 19:
                        // draw self-crossing polygon using the alternate fill rule
                        gc.SetBrushStyle(CGraphicsContext::EDiamondCrossHatchBrush);
                        gc.SetBrushColor(black);
                        gc.DrawPolygon(mypoints,CGraphicsContext::EAlternate);
                        break;
                case 20:
                        {
                        // draw self-crossing polygon using the alternate fill rule,
                        // and copy the lhs to the rhs of the screen
                        gc.SetBrushStyle(CGraphicsContext::EDiamondCrossHatchBrush);
                        gc.SetBrushColor(black);
                        gc.DrawPolygon(mypoints,CGraphicsContext::EAlternate);
                        TPoint screenOrigin(0,0); // top left of the screen
                        TSize halfScreenLR(320,240); // size of vertical half of screen
                        rect.SetRect(screenOrigin,halfScreenLR); // lhs of screen
                        TPoint offset(halfScreenLR.iWidth,0); // half screen width offset
                        gc.CopyRect(offset,rect); //  copy lhs of screen to rhs
                        }
                        break;
                case 21:
                        // draw some text left justified in a box,
                        // offset so text is just inside top of box
                        {
                        CFont* font=iMessageFont; // get the system message font
                        TInt fontAscent(font->AscentInPixels()); // system message font ascent
                        offset=fontAscent+3; // add a 3 pixel text line spacing
                        TInt margin=2; // left margin is two pixels
                        gc.SetBrushStyle(CGraphicsContext::ESolidBrush);
                        gc.SetBrushColor(darkGray);
                        gc.SetPenColor(white);
                        gc.UseFont(iMessageFont);
                        gc.DrawText(KTxtDrawCase21,box,offset,CGraphicsContext::ELeft,margin);
                        }
                        break;
                case 22:
                        // draw some text centered in a box, (margin is zero)
                        {
                        TInt boxHeight=box.Height(); // get height of text box
                        CFont* font=iMessageFont; // get the system message font
                        TInt textHeight(font->HeightInPixels()); // system message font height
                        offset=(textHeight+boxHeight)/2; // 1/2 font ht below halfway down box
                        TInt margin=0; // margin is zero
                        gc.SetBrushStyle(CGraphicsContext::ESolidBrush);
                        gc.SetBrushColor(black);
                        gc.SetPenColor(white);
                        gc.UseFont(iMessageFont);
                        gc.DrawText(KTxtDrawCase22,box,offset,CGraphicsContext::ECenter,margin);
                        }
                        break;
                case 23:
                        // draw some text right justified in a box,
                        // offset so text is just inside bottom of box
                        {
                        TInt boxHeight=box.Height(); // get height of text box
                        CFont* font=iMessageFont; // get the system message font
                        TInt fontDescent=font->DescentInPixels(); // system message font descent
                        offset=boxHeight-fontDescent-3;// offset, 3 pixel text line spacing 
                        TInt margin=2; // right margin is two pixels
                        gc.SetBrushStyle(CGraphicsContext::ESolidBrush);
                        gc.SetBrushColor(liteGray);
                        gc.SetPenColor(darkGray);
                        gc.UseFont(iMessageFont);
                        gc.DrawText(KTxtDrawCase23,box,offset,CGraphicsContext::ERight,margin);
                        }
                        break;
                case 24:
                        {
                        // draw a cross-hatched box
                        // then clear a small central rectangle
                        gc.SetBrushColor(darkGray);
                        gc.SetBrushStyle(CGraphicsContext::ESquareCrossHatchBrush);
                        gc.DrawRect(rect);
                        // clear a small rectangle
                        gc.SetBrushColor(liteGray); // change the brush color
                        gc.Clear(tinyBox); // clear to brush color
                        }
                        break;
                case 25:
                        {
                        // draw a cross-hatched box
                        // then clear a small central rectangle
                        // and write some text in it in smallest Swiss font,
                        // (which is actually a tiny "block" print-preview font)
                        // starting bottom left (illustrating flicker, overlap, mess)
                        gc.SetBrushColor(darkGray);
                        gc.SetBrushStyle(CGraphicsContext::ESquareCrossHatchBrush);
                        gc.DrawRect(rect);
                        // clear a small rectangle
                        gc.SetBrushColor(liteGray); // change the brush color
                        gc.Clear(tinyBox); // clear to brush color
                        // get an alternative font
                        CFont* myFont;
                        _LIT(KTxtArial,"Arial");
                        TFontSpec myFontSpec(KTxtArial,1); // to get smallest Arial font
                        CGraphicsDevice* screenDevice=(iCoeEnv->ScreenDevice());
                        screenDevice->GetNearestFontInTwips(myFont,myFontSpec);
                        gc.UseFont(myFont);
                        // set the text drawing position & draw (demonstrating flicker)
                        TInt fontDescent=myFont->DescentInPixels();
                        TPoint pos(0,tinyBox.Height()-fontDescent);
                        pos+=tinyBox.iTl;
                        gc.DrawText(KTxtDrawCase25,pos);
                        // discard and destroy the font
                        gc.DiscardFont();
                        screenDevice->ReleaseFont(myFont);
                        }
                        break;
                default:
                        break;
                }
        delete mypoints; // an array must be destroyed after use
        }

static CArrayFix<TPoint>* CreatePointsArrayL()
        {
        CArrayFixFlat<TPoint>* pointsArray = new CArrayFixFlat<TPoint>(5);
        
        TPoint point1(20,20);
        TPoint point2(100,190);
        TPoint point3(110,90);
        TPoint point4(50,150);
        TPoint point5(200,150);
        
        pointsArray->AppendL(point1);
        pointsArray->AppendL(point2);
        pointsArray->AppendL(point3);
        pointsArray->AppendL(point4);
        pointsArray->AppendL(point5);
        
        return pointsArray;
        }

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