// ShowInitIcon - version 1.0.1, May 30th, 1995
// This code is intended to let INIT writers easily display an icon at startup time.
// View in Geneva 9pt, 4-space tabs
// Written by: Peter N Lewis <peter@mail.peter.com.au>, Jim Walker <JWWalker@aol.com>
// and François Pottier <pottier@dmi.ens.fr>, with thanks to previous ShowINIT authors.
// Send comments and bug reports to François Pottier.
// This version features:
// - Short and readable code.
// - Correctly wraps around when more than one row of icons has been displayed.
// - works with System 6
// - Built with Universal Headers & CodeWarrior. Should work with other headers/compilers.
#include <Memory.h>
#include <Resources.h>
#include <Icons.h>
#include <OSUtils.h>
#include "ShowInitIcon.h"
// You should set SystemSixOrLater in your headers to avoid including glue for SysEnvirons.
// ---------------------------------------------------------------------------------------------------------------------
// Set this flag to 1 if you want to compile this file into a stand-alone resource (see note below).
// Set it to 0 if you want to include this source file into your INIT project.
#if 0
#define ShowInitIcon main
#endif
// ---------------------------------------------------------------------------------------------------------------------
// The ShowINIT mechanism works by having each INIT read/write data from these globals.
// The MPW C compiler doesn't accept variables declared at an absolute address, so I use these macros instead.
// Only one macro is defined per variable; there is no need to define a Set and a Get accessor like in <LowMem.h>.
#define LMVCheckSum (*(unsigned short*) 0x928)
#define LMVCoord (*( short*) 0x92A)
#define LMHCoord (*( short*) 0x92C)
#define LMHCheckSum (*(unsigned short*) 0x92E)
// ---------------------------------------------------------------------------------------------------------------------
// Prototypes for the subroutines. The main routine comes first; this is necessary to make THINK C's "Custom Header" option work.
static unsigned short CheckSum (short x);
static void ComputeIconRect (Rect* iconRect, Rect* screenBounds);
static void AdvanceIconPosition (Rect* iconRect);
static void DrawBWIcon (short iconID, Rect *iconRect);
// ---------------------------------------------------------------------------------------------------------------------
// Main routine.
typedef struct {
QDGlobals qd; // Storage for the QuickDraw globals
long qdGlobalsPtr; // A5 points to this place; it will contain a pointer to qd
} QDStorage;
pascal void ShowInitIcon (short iconFamilyID, Boolean advance)
{
long oldA5; // Original value of register A5
QDStorage qds; // Fake QD globals
CGrafPort colorPort;
GrafPort bwPort;
Rect destRect;
SysEnvRec environment; // Machine configuration.
oldA5 = SetA5((long) &qds.qdGlobalsPtr); // Tell A5 to point to the end of the fake QD Globals
InitGraf(&qds.qd.thePort); // Initialize the fake QD Globals
SysEnvirons(curSysEnvVers, &environment); // Find out what kind of machine this is
ComputeIconRect(&destRect, &qds.qd.screenBits.bounds); // Compute where the icon should be drawn
if (environment.systemVersion >= 0x0700 && environment.hasColorQD) {
OpenCPort(&colorPort);
PlotIconID(&destRect, atNone, ttNone, iconFamilyID);
CloseCPort(&colorPort);
}
else {
OpenPort(&bwPort);
DrawBWIcon(iconFamilyID, &destRect);
ClosePort(&bwPort);
}
if (advance)
AdvanceIconPosition (&destRect);
SetA5(oldA5); // Restore A5 to its previous value
}
// ---------------------------------------------------------------------------------------------------------------------
// A checksum is used to make sure that the data in there was left by another ShowINIT-aware INIT.
static unsigned short CheckSum (short x)
{
return (unsigned short)(((x << 1) | (x >> 15)) ^ 0x1021);
}
// ---------------------------------------------------------------------------------------------------------------------
// ComputeIconRect computes where the icon should be displayed.
static void ComputeIconRect (Rect* iconRect, Rect* screenBounds)
{
if (CheckSum(LMHCoord) != LMHCheckSum) // If we are first, we need to initialize the shared data.
LMHCoord = 8;
if (CheckSum(LMVCoord) != LMVCheckSum)
LMVCoord = (short)(screenBounds->bottom - 40);
if (LMHCoord + 34 > screenBounds->right) { // Check whether we must wrap
iconRect->left = 8;
iconRect->top = (short)(LMVCoord - 40);
}
else {
iconRect->left = LMHCoord;
iconRect->top = LMVCoord;
}
iconRect->right = (short)(iconRect->left + 32);
iconRect->bottom = (short)(iconRect->top + 32);
}
// AdvanceIconPosition updates the shared global variables so that the next extension will draw its icon beside ours.
static void AdvanceIconPosition (Rect* iconRect)
{
LMHCoord = (short)(iconRect->left + 40); // Update the shared data
LMVCoord = iconRect->top;
LMHCheckSum = CheckSum(LMHCoord);
LMVCheckSum = CheckSum(LMVCoord);
}
// DrawBWIcon draws the 'ICN#' member of the icon family. It works under System 6.
static void DrawBWIcon (short iconID, Rect *iconRect)
{
Handle icon;
BitMap source, destination;
GrafPtr port;
icon = Get1Resource('ICN#', iconID);
if (icon != NULL) {
HLock(icon);
// Prepare the source and destination bitmaps.
source.baseAddr = *icon + 128; // Mask address.
source.rowBytes = 4;
SetRect(&source.bounds, 0, 0, 32, 32);
GetPort(&port);
destination = port->portBits;
// Transfer the mask.
CopyBits(&source, &destination, &source.bounds, iconRect, srcBic, nil);
// Then the icon.
source.baseAddr = *icon;
CopyBits(&source, &destination, &source.bounds, iconRect, srcOr, nil);
}
}
// ---------------------------------------------------------------------------------------------------------------------
// Notes
// Checking for PlotIconID:
// We (PNL) now check for system 7 and colour QD, and use colour graf ports and PlotIconID only if both are true
// Otherwise we use B&W grafport and draw using PlotBWIcon.
