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Retired Document

Important: This sample code may not represent best practices for current development. The project may use deprecated symbols and illustrate technologies and techniques that are no longer recommended.

•QTMusic Sample Keyboards/EasyKeyboardDiagram.c

/*

    File:       KeyboardDiagram.c

    Modified version from the one in the warhol project

*/

#include <Memory.h>

#include <QuickDraw.h>

#include <Resources.h>

#include "EasyKeyboardDiagram.h"

static Handle GetAndDetachResource(ResType type,short id);

#define kBlackKeyBottom 16

static Handle GetAndDetachResource(ResType type,short id)

    Handle h;

    h = GetResource(type,id);

    DetachResource(h);

    return h;

void InitializeKeyboard(KeyboardDiagram *kd,Rect *r,short octaveCount,short lowKey)

    short i;

    kd->r = *r;

    kd->octaveCount = octaveCount;

    kd->keyCount = octaveCount * 12;

    if(lowKey >= 128)

        kd->mod = true;

        kd->modOffset = ((lowKey + kd->keyCount - 1) / kd->keyCount) * kd->keyCount;

        lowKey &= 127;

    else

        kd->mod = false;

    kd->lowKey = lowKey;

    for(i = 0; i < 128; i++)

        kd->keyVel[i] = 0;

    kd->whiteKey = (short **)GetAndDetachResource('Junk',kJunkWhite);

    kd->keyRight = (short **)GetAndDetachResource('Junk',kJunkBlack);

void TerminateKeyboard(KeyboardDiagram *kd)

    DisposeHandle((Handle)kd->whiteKey);

    DisposeHandle((Handle)kd->keyRight);

void SetKeyboardTopLeft(KeyboardDiagram *kd,short top, short left)

    OffsetRect(&kd->r, left - kd->r.left, top - kd->r.top);

void DrawKeyboardPiece(KeyboardDiagram *kd, short octave)

    Rect r;

    short w;

    PicHandle pH;

    PenNormal();

    pH = (PicHandle)Get1Resource('PICT',kKeyboardPict);

    if(pH)

        r = (**pH).picFrame;

        w = r.right - r.left-1;

        OffsetRect(&r,kd->r.left - r.left + w * octave,kd->r.top - r.top);

        DrawPicture(pH,&r);

        if(kd->gray)

            GoGray();

            PenMode(patBic);

            r.right += 2;

            r.bottom += 2;

            PaintRect(&r);

            PenNormal();

void DrawKeyboardDropShadow(KeyboardDiagram *kd)

    MoveTo(kd->r.left + 3,kd->r.bottom);

    LineTo(kd->r.right,kd->r.bottom);

    LineTo(kd->r.right,kd->r.top + 3);

void DrawKeyboard(KeyboardDiagram *kd)

    short i;

    DrawKeyboardDropShadow(kd);

    for(i = 0; i < kd->octaveCount; i++)

        DrawKeyboardPiece(kd,i);

void SetKeyboardGray(KeyboardDiagram *kd,Boolean gray)

    if(kd->gray != gray)

        kd->gray = gray;

        DrawKeyboard(kd);

void PaintKeyboardKey(KeyboardDiagram *kd,short pitch,short gray)

/*

 * 0-255, gray; -1, invert; -2, forecolor

*/

    short i,k;

    short octave;

    Rect r1,r2;

    Boolean blackKey;

    if(kd->gray)

        goto goHome;

    r1.left = r1.right = 0;

    r2.left = r2.right = 0;

    pitch -= kd->lowKey;

    if(pitch < 0 || pitch >= kd->keyCount)

        goto goHome;

    octave = pitch / 12;

    pitch = pitch % 12;

    blackKey = false;

    if(pitch == 1 || pitch == 3

            || pitch == 6 || pitch == 8 || pitch == 10)

/*

         * Black Keys

*/

        blackKey = true;

        r1.left = kd->r.left + (*kd->keyRight)[pitch - 1] + 2;

        r1.top = kd->r.top + 3;

        r1.right = kd->r.left + (*kd->keyRight)[pitch];

        r1.bottom = kd->r.top + kBlackKeyBottom;

    else

/*

         * White Keys

*/

        k = kd->r.left + 2;

        i = 0;

        while((*kd->whiteKey)[i] != pitch)

            i++;

            k += 9;

        r1.left = k;

        r1.top = kd->r.top + kBlackKeyBottom + 2;

        r1.right = k+6;

        r1.bottom = kd->r.bottom - 1;

        if(pitch)

            r2.left = kd->r.left + (*kd->keyRight)[pitch - 1] + 2;

        else

            r2.left = kd->r.left + 2;

        r2.top = kd->r.top + 2;

        r2.right = kd->r.left + (*kd->keyRight)[pitch];

        r2.bottom = kd->r.top + kBlackKeyBottom + 2;

/*

         * This is cheesy and proves I have

         * no idea what I am doing. - dvb

*/

        if(pitch == 5)

            r2.left ++;

        else if(pitch == 11)

            r2.right --;

    OffsetRect(&r1,octave * 63,0);

    OffsetRect(&r2,octave * 63,0);

    if(gray >=0)

        RGBColor c;

        if(!blackKey)

            gray = 255 - gray;

        c.blue = c.green = c.red = (((unsigned short)gray)<<8) | gray;

        RGBForeColor(&c);

    if(gray == -1)

        InvertRect(&r1);

        InvertRect(&r2);

    else

        PaintRect(&r1);

        PaintRect(&r2);

goHome:

    ForeColor(blackColor);

    PenNormal();

void PaintKeyboardVector(KeyboardDiagram *kd,unsigned char *keyVel)

    short i;

    unsigned char *w1,*w2;

    long x;

    w1 = keyVel;

    w2 = kd->keyVel;

    for(i = 0; i < 128; i++)

        x = *w1;

        if(*w2 != x)

            *w2 = x;

            x = x ? x+128:0;

            if( (i < kd->lowKey) || (i >= (kd->lowKey + kd->keyCount)) )

                if(kd->mod)

                    PaintKeyboardKey(kd,

                            (i+kd->modOffset)%(kd->keyCount)+kd->lowKey,x);

            PaintKeyboardKey(kd,i,x);

        w1++;

        w2++;

short GetKeyboardKey(KeyboardDiagram *kd,Point p)

/*

 * Return -1 if outside rectangle.

*/

    short pitch,octave;

    if(PtInRect(p,&kd->r))

        p.h -= kd->r.left;

        p.v -= kd->r.top;

        octave = p.h / 63;

        p.h %= 63;

        if(p.v > kBlackKeyBottom)

            pitch = (*kd->whiteKey)[p.h/9];

        else

            pitch = 0;

            while((*kd->keyRight)[pitch] < p.h)

                pitch++;

        pitch += octave*12;

        pitch += kd->lowKey;

    else

        pitch = -1;

    return pitch;

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