Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
On Sat, 2009-12-26 at 19:03 +0100, Louise Hoffman wrote: You can't show a drawable by itself, it needs to be in an image. Also, an image can't show itself, you must create a display for that. You are also using the API in weird ways, for example, objects such as layers and images are represented by integers in the plug-in context. You are also saying that the plug-in takes the active image and drawable as parameter, but since you are creating a new image, you are not interested in those values (I assume) so there is no point in specifying these as arguments to the hello-world procedure. This is my first attempt to write a GIMP plugin, as you probably have guessed by now =) I strongly suggest that you read the tutorial on developer.gimp.org then: http://developer.gimp.org/writing-a-plug-in/1/index.html and perhaps study the code of a plug-in that does something similar to what you want to achieve. Writing a plug-in without any idea of how the GIMP API works is not going to be a fun experience. Sven ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
No you got an error. 0, or FALSE, means error which you can read in the
documentation for the function:
http://developer.gimp.org/api/2.0/libgimp/libgimp-gimpdrawable.html#gimp-drawable-set-pixel
Now I see =) And now I get my red pixel as I wanted =)
gboolean s;
guint8 pixel[] = { 0xff, 0, 0, 0xff };
s = gimp_drawable_set_pixel (layer, 5, 5, 4, (guint8 *)pixel );
printf (Was the pixel set?: %i, s);
Full source at
http://pastebin.com/m35f95e3e
There you can also read that the num_channels parameter shall be the The
number of channels for the pixel.. You try to pass the number of bits, 24.
Even that is wrong since you create the layer with an alpha channel, so the
correct wrong thing to pass would be 32.
The thing is, what I would really like is to be able to plot 16bit
(doubles), but I can't figure out, how to put that in, when in my
case, pixel[], is guint8.
So if I set bpp to 32, and I have a 16bit value. How should I put that in?
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Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
I strongly suggest that you read the tutorial on developer.gimp.org then: http://developer.gimp.org/writing-a-plug-in/1/index.html I read that one, and it was from that, I copied a lot of the code. I was why I had all this pointer and structs at first =) and perhaps study the code of a plug-in that does something similar to what you want to achieve. Writing a plug-in without any idea of how the GIMP API works is not going to be a fun experience. hehe =) Yes, it is pretty tough, but you guys have helped me out a lot, so now I am very close to my goal =) I guess the biggest problem right now is, how I plot a 16bit value. Searching I find some that say GEGL will first be usable in GIMP 2.10. Have you had any experience with plotting 16 bit (doubles)? Can it be done? ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
On Sun, 2009-12-27 at 11:18 +0100, Louise Hoffman wrote: I strongly suggest that you read the tutorial on developer.gimp.org then: http://developer.gimp.org/writing-a-plug-in/1/index.html I read that one, and it was from that, I copied a lot of the code. I was why I had all this pointer and structs at first =) The code you showed us was definitely not copied from there. And it is correct to use the GimpDrawable struct from plug-ins. Martins advice that plug-ins would only refer to drawables by their integer ID is incorrect. Sven ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
Sven Neumann wrote: On Sun, 2009-12-27 at 11:18 +0100, Louise Hoffman wrote: I strongly suggest that you read the tutorial on developer.gimp.org then: http://developer.gimp.org/writing-a-plug-in/1/index.html I read that one, and it was from that, I copied a lot of the code. I was why I had all this pointer and structs at first =) The code you showed us was definitely not copied from there. And it is correct to use the GimpDrawable struct from plug-ins. Martins advice that plug-ins would only refer to drawables by their integer ID is incorrect. I would like to point out that the GimpDrawable struct in libgimp has a member gint32drawable_id; /* drawable ID */ so plug-ins still refers to drawables in the core through an ID, even though it might be indirectly through a pointer to the libgimp GimpDrawable structure. I agree however that my advice was misleading and stand corrected. / Martin -- My GIMP Blog: http://www.chromecode.com/ Best way to keep up with GIMP from git ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
Louise Hoffman wrote:
Dear developers,
I am trying to make a GIMP plugin that can open a new drawable on the
screen. Just like when you make one from File-New.
Hi!
You can't show a drawable by itself, it needs to be in an image. Also,
an image can't show itself, you must create a display for that. You are
also using the API in weird ways, for example, objects such as layers
and images are represented by integers in the plug-in context.
You are also saying that the plug-in takes the active image and drawable
as parameter, but since you are creating a new image, you are not
interested in those values (I assume) so there is no point in specifying
these as arguments to the hello-world procedure.
I have attached a rewritten version of main.c (called hello-world.c
since that is a name that doesn't conflict as much) that should do what
you want. You might also want to consider using a scripting language
like Scheme or Python for this.
/ Martin
--
My GIMP Blog:
http://www.chromecode.com/
Reducing UI clutter, docking bars removed
#include libgimp/gimp.h
static void
query (void)
{
static GimpParamDef args[] =
{
{
GIMP_PDB_INT32,
run-mode,
Run mode
},
};
gimp_install_procedure (
plug-in-hello,
Hello, world!,
Displays \Hello, world!\ in a dialog,
David Neary,
Copyright David Neary,
2004,
_Hello world...,
NULL,
GIMP_PLUGIN,
G_N_ELEMENTS (args), 0,
args, NULL);
gimp_plugin_menu_register (plug-in-hello,
Image/Filters/Misc);
}
static void
run (const gchar *name,
gint nparams,
const GimpParam *param,
gint *nreturn_vals,
GimpParam **return_vals)
{
static GimpParam values[1];
GimpPDBStatusType status = GIMP_PDB_SUCCESS;
GimpRunMode run_mode;
gint32image;
gint32layer;
gint32display;
/* Setting mandatory output values */
*nreturn_vals = 1;
*return_vals = values;
values[0].type = GIMP_PDB_STATUS;
values[0].data.d_status = status;
/* Getting run_mode - we won't display a dialog if
* we are in NONINTERACTIVE mode */
run_mode = param[0].data.d_int32;
image = gimp_image_new (800, 600, GIMP_RGB);
layer = gimp_layer_new (image,
foo,
800, 600,
GIMP_RGBA_IMAGE,
100.0,
GIMP_NORMAL_MODE);
gimp_image_add_layer (image, layer, 0);
display = gimp_display_new (image);
if (run_mode != GIMP_RUN_NONINTERACTIVE)
g_message(Hello, world!\n);
}
GimpPlugInInfo PLUG_IN_INFO =
{
NULL,
NULL,
query,
run
};
MAIN()
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Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
Quoting Louise Hoffman louise.hoff...@gmail.com: When I select the plugin in GIMP I get these errors: Calling error for procedure 'gimp-drawable-width': Procedure 'gimp-drawable-width' has been called with an invalid ID for argument 'drawable'. Most likely a plug-in is trying to work on a layer that doesn't exist any longer. ... Your invocation of 'gimp_install_procedure' specifies NULL for the image_type. This is probably what you want -- you don't need an image opened in order to create a new image -- but this means that you shouldn't be using GIMP_PDB_IMAGE and GIMP_PDB_DRAWABLE in your GimpParamDef (if there is no image open when you execute the plug-in, those parameters can't be provided). As a side note, I don't understand why you define your own 'MyDrawable' struct when it is identical to the GimpDrawable struct already available. ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
File-New creates a new image, not a new drawable. Okay, I had that mixed up. A new image is really what I wanted then =) ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
You can't show a drawable by itself, it needs to be in an image. Also, an
image can't show itself, you must create a display for that. You are also
using the API in weird ways, for example, objects such as layers and images
are represented by integers in the plug-in context.
You are also saying that the plug-in takes the active image and drawable as
parameter, but since you are creating a new image, you are not interested in
those values (I assume) so there is no point in specifying these as
arguments to the hello-world procedure.
This is my first attempt to write a GIMP plugin, as you probably have
guessed by now =)
I have attached a rewritten version of main.c (called hello-world.c since
that is a name that doesn't conflict as much) that should do what you want.
You might also want to consider using a scripting language like Scheme or
Python for this.
Wow. That's amazing. Thank you very much =)
What I ultimately would like to end up with is being able to set
pixels, the user makes changes to the image, and I read the pixels one
by one again.
So now I have tried to set a pixel like so
/* Trying to set a pixel at x=5,y=5 with value 150 */
GimpDrawable* drawable;
drawable = gimp_drawable_get (layer);
/* Trying to set a pixel at x=5,y=5 with value 150 in 24 bit color */
gboolean s;
s = gimp_drawable_set_pixel (drawable, 5, 5, 24, 150);
But when I compile I get:
hello-world.c:73: warning: passing argument 1 of
‘gimp_drawable_set_pixel’ makes integer from pointer without a cast
/usr/include/gimp-2.0/libgimp/gimpdrawable_pdb.h:89: note: expected
‘gint32’ but argument is of type ‘struct GimpDrawable *’
The code is attached. I am bit lost how to solve this.
Any help will be very appreciated =)
#include libgimp/gimp.h
static void
query (void)
{
static GimpParamDef args[] =
{
{
GIMP_PDB_INT32,
run-mode,
Run mode
},
};
gimp_install_procedure (
plug-in-hello,
Hello, world!,
Displays \Hello, world!\ in a dialog,
David Neary,
Copyright David Neary,
2004,
_Hello world...,
NULL,
GIMP_PLUGIN,
G_N_ELEMENTS (args), 0,
args, NULL);
gimp_plugin_menu_register (plug-in-hello,
Image/Filters/Misc);
}
static void
run (const gchar *name,
gint nparams,
const GimpParam *param,
gint *nreturn_vals,
GimpParam **return_vals)
{
static GimpParam values[1];
GimpPDBStatusType status = GIMP_PDB_SUCCESS;
GimpRunMode run_mode;
gint32image;
gint32layer;
gint32display;
/* Setting mandatory output values */
*nreturn_vals = 1;
*return_vals = values;
values[0].type = GIMP_PDB_STATUS;
values[0].data.d_status = status;
/* Getting run_mode - we won't display a dialog if
* we are in NONINTERACTIVE mode */
run_mode = param[0].data.d_int32;
image = gimp_image_new (800, 600, GIMP_RGB);
layer = gimp_layer_new (image,
foo,
800, 600,
GIMP_RGBA_IMAGE,
100.0,
GIMP_NORMAL_MODE);
gimp_image_add_layer (image, layer, 0);
/* Trying to set a pixel at x=5,y=5 with value 150 */
GimpDrawable* drawable;
drawable = gimp_drawable_get (layer);
/* Trying to set a pixel at x=5,y=5 with value 150 in 24 bit color */
gboolean s;
s = gimp_drawable_set_pixel (drawable, 5, 5, 24, 150);
display = gimp_display_new (image);
if (run_mode != GIMP_RUN_NONINTERACTIVE)
g_message(Hello, world!\n);
}
GimpPlugInInfo PLUG_IN_INFO =
{
NULL,
NULL,
query,
run
};
MAIN()
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Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
Your invocation of 'gimp_install_procedure' specifies NULL for the image_type. This is probably what you want -- you don't need an image opened in order to create a new image -- but this means that you shouldn't be using GIMP_PDB_IMAGE and GIMP_PDB_DRAWABLE in your GimpParamDef (if there is no image open when you execute the plug-in, those parameters can't be provided). As a side note, I don't understand why you define your own 'MyDrawable' struct when it is identical to the GimpDrawable struct already available. I thought that was how a new image was created =) ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
Louise Hoffman wrote: hello-world.c:73: warning: passing argument 1 of ‘gimp_drawable_set_pixel’ makes integer from pointer without a cast /usr/include/gimp-2.0/libgimp/gimpdrawable_pdb.h:89: note: expected ‘gint32’ but argument is of type ‘struct GimpDrawable *’ As I said, in the plug-in context layers (and drawables) are identified by integers, not pointers. Looks like you try to use a struct pointer again. Plug-ins run in their own process and thus pointer-passing doesn't work. / Martin -- My GIMP Blog: http://www.chromecode.com/ Best way to keep up with GIMP from git ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
As I said, in the plug-in context layers (and drawables) are identified by integers, not pointers. Looks like you try to use a struct pointer again. Plug-ins run in their own process and thus pointer-passing doesn't work. Sorry about that. Now I don't get any errors, but I don't see the pixel either... /* Trying to set a pixel at x=5,y=5 with value 150 in 24 bit color */ const guint8 *pixel; pixel = (guint8 *) 150; gboolean s; s = gimp_drawable_set_pixel (layer, 5, 5, 24, pixel); printf (Was the pixel set?: %i, s); and s returns 0. Is it how I define the pixel value that is the problem? The hello-world.c is here with my change http://pastebin.com/m39f62a20 ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Plugin that can open a drawable on screen. What am I doing wrong?
Louise Hoffman wrote: Now I don't get any errors, but I don't see the pixel either... /* Trying to set a pixel at x=5,y=5 with value 150 in 24 bit color */ const guint8 *pixel; pixel = (guint8 *) 150; gboolean s; s = gimp_drawable_set_pixel (layer, 5, 5, 24, pixel); printf (Was the pixel set?: %i, s); Hi again! No you got an error. 0, or FALSE, means error which you can read in the documentation for the function: http://developer.gimp.org/api/2.0/libgimp/libgimp-gimpdrawable.html#gimp-drawable-set-pixel There you can also read that the num_channels parameter shall be the The number of channels for the pixel.. You try to pass the number of bits, 24. Even that is wrong since you create the layer with an alpha channel, so the correct wrong thing to pass would be 32. / Martin -- My GIMP Blog: http://www.chromecode.com/ Reducing UI clutter, docking bars removed ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
