X/* Exported entries */XX/* Section 1 -- Basic functions from graphics.h */XX/*X * Function: InitGraphicsX * ----------------------X * The implementation below hides considerable complexity underneathX * the InitXHandler call.  If you are trying to modify or maintainX * this implementation, it is important to understand how thatX * function is implemented.  For details, see the xhandler.cX * implementation.X */XXvoid InitGraphics(void)X{X    if (initialized) {X        XMSendCommand(ClearCmd, "");X    } else {X        initialized = TRUE;X        ProtectVariable(stateStack);X        ProtectVariable(windowTitle);X        ProtectVariable(textFont);X        XDSetWindowSize(windowWidth, windowHeight);X        XMInitialize(windowTitle);X        InitColors();X    }X    InitGraphicsState();X}XXvoid MovePen(double x, double y)X{X    InitCheck();X    if (regionState == RegionActive) regionState = PenHasMoved;X    cx = x;X    cy = y;X}XXvoid DrawLine(double dx, double dy)X{X    InitCheck();X    switch (regionState) {X      case NoRegion: case RegionActive:X        break;X      case RegionStarting:X        regionState = RegionActive;X        break;X      case PenHasMoved:X        Error("Region segments must be contiguous");X    }X    sprintf(cmdBuffer, "%.12g %.12g %.12g %.12g", cx, cy, dx, dy);X    XMSendCommand(LineCmd, cmdBuffer);X    cx += dx;X    cy += dy;X}XXvoid DrawArc(double r, double start, double sweep)X{X    DrawEllipticalArc(r, r, start, sweep);X}XXdouble GetWindowWidth(void)X{X    return (windowWidth);X}XXdouble GetWindowHeight(void)X{X    return (windowHeight);X}XXdouble GetCurrentX(void)X{X    InitCheck();X    return (cx);X}XXdouble GetCurrentY(void)X{X    InitCheck();X    return (cy);X}XX/* Section 2 -- Elliptical arcs */XXvoid DrawEllipticalArc(double rx, double ry,X                       double start, double sweep)X{X    double x, y;XX    InitCheck();X    switch (regionState) {X      case NoRegion: case RegionActive:X        break;X      case RegionStarting:X        regionState = RegionActive;X        break;X      case PenHasMoved:X        Error("Region segments must be contiguous");X    }X    x = cx + rx * cos(GLRadians(start + 180));X    y = cy + ry * sin(GLRadians(start + 180));X    sprintf(cmdBuffer, "%.12g %.12g %.12g %.12g %.12g %.12g",X                       x, y, rx, ry, start, sweep);X    XMSendCommand(ArcCmd, cmdBuffer);X    cx = x + rx * cos(GLRadians(start + sweep));X    cy = y + ry * sin(GLRadians(start + sweep));X}XX/* Section 3 -- Graphical structures */XXvoid StartFilledRegion(double density)X{X    InitCheck();X    if (regionState != NoRegion) {X        Error("Region is already in progress");X    }X    if (density < 0 || density > 1) {X        Error("Density for regions must be between 0 and 1");X    }X    regionState = RegionStarting;X    sprintf(cmdBuffer, "%.12g", density);X    XMSendCommand(StartRegionCmd, cmdBuffer);X}XXvoid EndFilledRegion(void)X{X    InitCheck();X    if (regionState == NoRegion) {X        Error("EndFilledRegion without StartFilledRegion");X    }X    regionState = NoRegion;X    XMSendCommand(EndRegionCmd, "");X}XX/* Section 4 -- String functions */XXvoid DrawTextString(string text)X{X    InitCheck();X    if (regionState != NoRegion) {X        Error("Text strings are illegal inside a region");X    }X    if (strlen(text) > MaxTextString) {X        Error("Text string too long");X    }X    InstallFont();X    sprintf(cmdBuffer, "%.12g %.12g %s", cx, cy, text);X    XMSendCommand(TextCmd, cmdBuffer);X    cx += TextStringWidth(text);X}XXdouble TextStringWidth(string text)X{X    double result;XX    InitCheck();X    if (strlen(text) > MaxTextString) {X        Error("Text string too long");X    }X    InstallFont();X    sprintf(cmdBuffer, "%s", text);X    XMSendCommand(WidthCmd, cmdBuffer);X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%lg", &result);X    return (result);X}XXvoid SetFont(string font)X{X    InitCheck();X    if (strlen(font) > MaxFontName) Error("Font name too long");X    textFont = CopyString(font);X    fontChanged = TRUE;X}XXstring GetFont(void)X{X    InitCheck();X    InstallFont();X    return (CopyString(textFont));X}XXvoid SetPointSize(int size)X{X    InitCheck();X    pointSize = size;X    fontChanged = TRUE;X}XXint GetPointSize(void)X{X    InitCheck();X    InstallFont();X    return (pointSize);X}XXvoid SetStyle(int style)X{X    InitCheck();X    textStyle = style;X    fontChanged = TRUE;X}XXint GetStyle(void)X{X    InitCheck();X    InstallFont();X    return (textStyle);X}XXdouble GetFontAscent(void)X{X    double ascent;XX    InitCheck();X    InstallFont();X    XMSendCommand(FontMetricsCmd, "");X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%lg", &ascent);X    return (ascent);X}XXdouble GetFontDescent(void)X{X    double descent;XX    InitCheck();X    InstallFont();X    XMSendCommand(FontMetricsCmd, "");X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%*lg %lg", &descent);X    return (descent);X}XXdouble GetFontHeight(void)X{X    double height;XX    InitCheck();X    InstallFont();X    XMSendCommand(FontMetricsCmd, "");X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%*lg %*lg %lg", &height);X    return (height);X}XX/* Section 5 -- Mouse support */XXdouble GetMouseX(void)X{X    double x, y;X    int state;XX    InitCheck();X    XMSendCommand(GetMouseCmd, "");X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%d, %lg, %lg", &state, &x, &y);X    return (x);X}XXdouble GetMouseY(void)X{X    string line;X    double x, y;X    int state;XX    InitCheck();X    XMSendCommand(GetMouseCmd, "");X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%d, %lg, %lg", &state, &x, &y);X    return (y);X}XXbool MouseButtonIsDown(void)X{X    string line;X    double x, y;X    int state;XX    InitCheck();X    XMSendCommand(GetMouseCmd, "");X    XMGetResponse(cmdBuffer);X    (void) sscanf(cmdBuffer, "%d, %lg, %lg", &state, &x, &y);X    return (state != 0);X}XXvoid WaitForMouseDown(void)X{X    InitCheck();X    XMSendCommand(WaitForMouseCmd, "D");X    XMGetResponse(cmdBuffer);X}XXvoid WaitForMouseUp(void)X{X    InitCheck();X    XMSendCommand(WaitForMouseCmd, "U");X    XMGetResponse(cmdBuffer);X}XX/* Section 6 -- Color support */XXbool HasColor(void)X{X    InitCheck();X    return (colorOK);X}XXvoid SetPenColor(string color)X{X    int cindex;XX    InitCheck();X    cindex = FindColorName(color);X    if (cindex == -1) Error("Undefined color: %s", color);X    penColor = cindex;X    if (penColor == lastColor) return;X    lastColor = penColor;X    if (HasColor()) {X        sprintf(cmdBuffer, "%g %g %g\n",X                colorTable[cindex].red,X                colorTable[cindex].green,X                colorTable[cindex].blue);X        XMSendCommand(SetColorCmd, cmdBuffer);X    } else {X        SetEraseMode(eraseMode);X    }X}XXstring GetPenColor(void)X{X    InitCheck();X    return (colorTable[penColor].name);X}XXvoid DefineColor(string name,X                 double red, double green, double blue)X{X    int cindex;XX    InitCheck();X    if (red < 0 || red > 1 || green < 0 || green > 1 || blue < 0 || blue > 1) {X        Error("DefineColor: All color intensities must be between 0 and 1");X    }X    cindex = FindColorName(name);X    if (cindex == -1) {X        if (nColors == MaxColors) Error("DefineColor: Too many colors");X        cindex = nColors++;X    }X    colorTable[cindex].name = CopyString(name);X    colorTable[cindex].red = red;X    colorTable[cindex].green = green;X    colorTable[cindex].blue = blue;X}XX/* Section 7 -- Miscellaneous functions */XXvoid SetEraseMode(bool mode)X{X    InitCheck();X    eraseMode = mode;X    sprintf(cmdBuffer, "%d", (int) (mode || ShouldBeWhite()));X    XMSendCommand(SetEraseCmd, cmdBuffer);X}XXbool GetEraseMode(void)X{X    InitCheck();X    return (eraseMode);X}XXvoid SetWindowTitle(string title)X{X    windowTitle = CopyString(title);X    if (initialized) {X        sprintf(cmdBuffer, "%s", windowTitle);X        XMSendCommand(SetTitleCmd, cmdBuffer);X    }X}XXstring GetWindowTitle(void)X{X    return (CopyString(windowTitle));X}XXvoid UpdateDisplay(void)X{X    int cnt;XX    InitCheck();X    XMSendCommand(UpdateCmd, "");X}XXvoid Pause(double seconds)X{X    if (initialized) UpdateDisplay();X    USleep((unsigned) (seconds * 1000000));X}XXvoid ExitGraphics(void)X{X    XMSendCommand(ExitGraphicsCmd, "");X    exit(0);X}XXvoid SaveGraphicsState(void)X{X    graphicsStateT sb;XX    InitCheck();X    sb = New(graphicsStateT);X    sb->cx = cx;X    sb->cy = cy;X    sb->font = textFont;X    sb->size = pointSize;X    sb->style = textStyle;X    sb->erase = eraseMode;X    sb->color = penColor;X    sb->link = stateStack;X    stateStack = sb;X}XXvoid RestoreGraphicsState(void)X{X    graphicsStateT sb;XX    InitCheck();X    if (stateStack == NULL) {X        Error("RestoreGraphicsState called before SaveGraphicsState");X    }X    sb = stateStack;X    cx = sb->cx;X    cy = sb->cy;X    textFont = sb->font;X    pointSize = sb->size;X    textStyle = sb->style;X    eraseMode = sb->erase;X    penColor = sb->color;X    stateStack = sb->link;X    FreeBlock(sb);X    fontChanged = TRUE;X    SetEraseMode(eraseMode);X    SetPenColor(colorTable[penColor].name);X}XXdouble GetFullScreenWidth(void)X{X    double screenWidth, screenHeight;XX    XDG