1 /*

     2  * Copyright 1999-2001 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 #ifndef _JAVASOFT_JAWT_H_

    27 #define _JAVASOFT_JAWT_H_

    28 

    29 #include "jni.h"

    30 

    31 #ifdef __cplusplus

    32 extern "C" {

    33 #endif

    34 

    35 /*

    36  * AWT native interface (new in JDK 1.3)

    37  *

    38  * The AWT native interface allows a native C or C++ application a means

    39  * by which to access native structures in AWT.  This is to facilitate moving

    40  * legacy C and C++ applications to Java and to target the needs of the

    41  * community who, at present, wish to do their own native rendering to canvases

    42  * for performance reasons.  Standard extensions such as Java3D also require a

    43  * means to access the underlying native data structures of AWT.

    44  *

    45  * There may be future extensions to this API depending on demand.

    46  *

    47  * A VM does not have to implement this API in order to pass the JCK.

    48  * It is recommended, however, that this API is implemented on VMs that support

    49  * standard extensions, such as Java3D.

    50  *

    51  * Since this is a native API, any program which uses it cannot be considered

    52  * 100% pure java.

    53  */

    54 

    55 /*

    56  * AWT Native Drawing Surface (JAWT_DrawingSurface).

    57  *

    58  * For each platform, there is a native drawing surface structure.  This

    59  * platform-specific structure can be found in jawt_md.h.  It is recommended

    60  * that additional platforms follow the same model.  It is also recommended

    61  * that VMs on Win32 and Solaris support the existing structures in jawt_md.h.

    62  *

    63  *******************

    64  * EXAMPLE OF USAGE:

    65  *******************

    66  *

    67  * In Win32, a programmer wishes to access the HWND of a canvas to perform

    68  * native rendering into it.  The programmer has declared the paint() method

    69  * for their canvas subclass to be native:

    70  *

    71  *

    72  * MyCanvas.java:

    73  *

    74  * import java.awt.*;

    75  *

    76  * public class MyCanvas extends Canvas {

    77  *

    78  *     static {

    79  *         System.loadLibrary("mylib");

    80  *     }

    81  *

    82  *     public native void paint(Graphics g);

    83  * }

    84  *

    85  *

    86  * myfile.c:

    87  *

    88  * #include "jawt_md.h"

    89  * #include <assert.h>

    90  *

    91  * JNIEXPORT void JNICALL

    92  * Java_MyCanvas_paint(JNIEnv* env, jobject canvas, jobject graphics)

    93  * {

    94  *     JAWT awt;

    95  *     JAWT_DrawingSurface* ds;

    96  *     JAWT_DrawingSurfaceInfo* dsi;

    97  *     JAWT_Win32DrawingSurfaceInfo* dsi_win;

    98  *     jboolean result;

    99  *     jint lock;

   100  *

   101  *     // Get the AWT

   102  *     awt.version = JAWT_VERSION_1_3;

   103  *     result = JAWT_GetAWT(env, &awt);

   104  *     assert(result != JNI_FALSE);

   105  *

   106  *     // Get the drawing surface

   107  *     ds = awt.GetDrawingSurface(env, canvas);

   108  *     assert(ds != NULL);

   109  *

   110  *     // Lock the drawing surface

   111  *     lock = ds->Lock(ds);

   112  *     assert((lock & JAWT_LOCK_ERROR) == 0);

   113  *

   114  *     // Get the drawing surface info

   115  *     dsi = ds->GetDrawingSurfaceInfo(ds);

   116  *

   117  *     // Get the platform-specific drawing info

   118  *     dsi_win = (JAWT_Win32DrawingSurfaceInfo*)dsi->platformInfo;

   119  *

   120  *     //////////////////////////////

   121  *     // !!! DO PAINTING HERE !!! //

   122  *     //////////////////////////////

   123  *

   124  *     // Free the drawing surface info

   125  *     ds->FreeDrawingSurfaceInfo(dsi);

   126  *

   127  *     // Unlock the drawing surface

   128  *     ds->Unlock(ds);

   129  *

   130  *     // Free the drawing surface

   131  *     awt.FreeDrawingSurface(ds);

   132  * }

   133  *

   134  */

   135 

   136 /*

   137  * JAWT_Rectangle

   138  * Structure for a native rectangle.

   139  */

   140 typedef struct jawt_Rectangle {

   141     jint x;

   142     jint y;

   143     jint width;

   144     jint height;

   145 } JAWT_Rectangle;

   146 

   147 struct jawt_DrawingSurface;

   148 

   149 /*

   150  * JAWT_DrawingSurfaceInfo

   151  * Structure for containing the underlying drawing information of a component.

   152  */

   153 typedef struct jawt_DrawingSurfaceInfo {

   154     /*

   155      * Pointer to the platform-specific information.  This can be safely

   156      * cast to a JAWT_Win32DrawingSurfaceInfo on Windows or a

   157      * JAWT_X11DrawingSurfaceInfo on Solaris.  See jawt_md.h for details.

   158      */

   159     void* platformInfo;

   160     /* Cached pointer to the underlying drawing surface */

   161     struct jawt_DrawingSurface* ds;

   162     /* Bounding rectangle of the drawing surface */

   163     JAWT_Rectangle bounds;

   164     /* Number of rectangles in the clip */

   165     jint clipSize;

   166     /* Clip rectangle array */

   167     JAWT_Rectangle* clip;

   168 } JAWT_DrawingSurfaceInfo;

   169 

   170 #define JAWT_LOCK_ERROR                 0x00000001

   171 #define JAWT_LOCK_CLIP_CHANGED          0x00000002

   172 #define JAWT_LOCK_BOUNDS_CHANGED        0x00000004

   173 #define JAWT_LOCK_SURFACE_CHANGED       0x00000008

   174 

   175 /*

   176  * JAWT_DrawingSurface

   177  * Structure for containing the underlying drawing information of a component.

   178  * All operations on a JAWT_DrawingSurface MUST be performed from the same

   179  * thread as the call to GetDrawingSurface.

   180  */

   181 typedef struct jawt_DrawingSurface {

   182     /*

   183      * Cached reference to the Java environment of the calling thread.

   184      * If Lock(), Unlock(), GetDrawingSurfaceInfo() or

   185      * FreeDrawingSurfaceInfo() are called from a different thread,

   186      * this data member should be set before calling those functions.

   187      */

   188     JNIEnv* env;

   189     /* Cached reference to the target object */

   190     jobject target;

   191     /*

   192      * Lock the surface of the target component for native rendering.

   193      * When finished drawing, the surface must be unlocked with

   194      * Unlock().  This function returns a bitmask with one or more of the

   195      * following values:

   196      *

   197      * JAWT_LOCK_ERROR - When an error has occurred and the surface could not

   198      * be locked.

   199      *

   200      * JAWT_LOCK_CLIP_CHANGED - When the clip region has changed.

   201      *

   202      * JAWT_LOCK_BOUNDS_CHANGED - When the bounds of the surface have changed.

   203      *

   204      * JAWT_LOCK_SURFACE_CHANGED - When the surface itself has changed

   205      */

   206     jint (JNICALL *Lock)

   207         (struct jawt_DrawingSurface* ds);

   208     /*

   209      * Get the drawing surface info.

   210      * The value returned may be cached, but the values may change if

   211      * additional calls to Lock() or Unlock() are made.

   212      * Lock() must be called before this can return a valid value.

   213      * Returns NULL if an error has occurred.

   214      * When finished with the returned value, FreeDrawingSurfaceInfo must be

   215      * called.

   216      */

   217     JAWT_DrawingSurfaceInfo* (JNICALL *GetDrawingSurfaceInfo)

   218         (struct jawt_DrawingSurface* ds);

   219     /*

   220      * Free the drawing surface info.

   221      */

   222     void (JNICALL *FreeDrawingSurfaceInfo)

   223         (JAWT_DrawingSurfaceInfo* dsi);

   224     /*

   225      * Unlock the drawing surface of the target component for native rendering.

   226      */

   227     void (JNICALL *Unlock)

   228         (struct jawt_DrawingSurface* ds);

   229 } JAWT_DrawingSurface;

   230 

   231 /*

   232  * JAWT

   233  * Structure for containing native AWT functions.

   234  */

   235 typedef struct jawt {

   236     /*

   237      * Version of this structure.  This must always be set before

   238      * calling JAWT_GetAWT()

   239      */

   240     jint version;

   241     /*

   242      * Return a drawing surface from a target jobject.  This value

   243      * may be cached.

   244      * Returns NULL if an error has occurred.

   245      * Target must be a java.awt.Component (should be a Canvas

   246      * or Window for native rendering).

   247      * FreeDrawingSurface() must be called when finished with the

   248      * returned JAWT_DrawingSurface.

   249      */

   250     JAWT_DrawingSurface* (JNICALL *GetDrawingSurface)

   251         (JNIEnv* env, jobject target);

   252     /*

   253      * Free the drawing surface allocated in GetDrawingSurface.

   254      */

   255     void (JNICALL *FreeDrawingSurface)

   256         (JAWT_DrawingSurface* ds);

   257     /*

   258      * Since 1.4

   259      * Locks the entire AWT for synchronization purposes

   260      */

   261     void (JNICALL *Lock)(JNIEnv* env);

   262     /*

   263      * Since 1.4

   264      * Unlocks the entire AWT for synchronization purposes

   265      */

   266     void (JNICALL *Unlock)(JNIEnv* env);

   267     /*

   268      * Since 1.4

   269      * Returns a reference to a java.awt.Component from a native

   270      * platform handle.  On Windows, this corresponds to an HWND;

   271      * on Solaris and Linux, this is a Drawable.  For other platforms,

   272      * see the appropriate machine-dependent header file for a description.

   273      * The reference returned by this function is a local

   274      * reference that is only valid in this environment.

   275      * This function returns a NULL reference if no component could be

   276      * found with matching platform information.

   277      */

   278     jobject (JNICALL *GetComponent)(JNIEnv* env, void* platformInfo);

   279 

   280 } JAWT;

   281 

   282 /*

   283  * Get the AWT native structure.  This function returns JNI_FALSE if

   284  * an error occurs.

   285  */

   286 _JNI_IMPORT_OR_EXPORT_

   287 jboolean JNICALL JAWT_GetAWT(JNIEnv* env, JAWT* awt);

   288 

   289 #define JAWT_VERSION_1_3 0x00010003

   290 #define JAWT_VERSION_1_4 0x00010004

   291 

   292 #ifdef __cplusplus

   293 } /* extern "C" */

   294 #endif

   295 

   296 #endif /* !_JAVASOFT_JAWT_H_ */