Re: [clutter] Using cogl without clutter
Oscar, On Wed, 2010-04-07 at 16:56 +0200, Oscar Lazzarino wrote: On Wed, Apr 7, 2010 at 4:43 PM, Neil Roberts n...@linux.intel.com wrote: You can't call the cogl_pango_* functions using a layout created with a regular pango context - instead it has to be a context created with the special Cogl font map. The cogl_pango functions in cogl-pango.h are meant to be public so it is safe to use them. The lack of documentation is an oversight not an attempt to hide them. The usual way to paint custom text in an actor is to call clutter_actor_create_pango_layout() and then render it with cogl_pango_render_layout(). This will take advantage of the CoglPango glyph cache and render the text from textures so it should be relatively efficient. Hope that helps - Neil I did as you said, and it works :) Actually, just out of curiosity, I also tried to create the Pango context like this PangoFontMap *lPangoFontMap = cogl_pango_font_map_new(); PangoContext *lPangoCtx = pango_font_map_create_context(lPangoFontMap); and it also works. Yes, it works. Your case is about interacting with Pango. Cogl is a wrapper of GL and GLES calls, if you try with GL or GLES specific call, you need a call to clutter_init to initialize the display. Thanks to everyone who answered :) O. Regards, -Hieu -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
Re: [clutter] Using cogl without clutter
On Tue, Apr 6, 2010 at 6:07 PM, Robert Bragg b...@o-hand.com wrote: The long term goal is for Cogl to become a standalone 3D graphics API and we are incrementally working towards this goal. Cogl will also have a window system abstraction (only as far as framebuffer management is concerned, I don't mean anything relating input events etc) that could make it possible to integrate tightly with GTK in one way or another. Integrating with a GL context not owned by Cogl adds additional complexity but theoretically it would be possible to create a Cogl winsys that allowed this. Sorry that doesn't really help you, but you might be interested to know it may be possible one day. OK, let's try lowering the bar ;-) Would it be possible to use cogl_pango outside of the clutter_text actor (i.e. in a custom actor)? The cogl_pango functions are treated as private functions and not documented, as far as I can see, and the simple approach CoglColor *lWhite = cogl_color_new(); cogl_color_set_from_4f(lWhite, 1.0, 1.0, 1.0, 1.0); cogl_set_source_color(lWhite); PangoContext *lPangoCtx = pango_context_new(); PangoFontDescription *lPangoFontDescr = pango_font_description_new(); pango_font_description_set_family(lPangoFontDescr, Sans); pango_font_description_set_size(lPangoFontDescr, 10 * PANGO_SCALE); PangoLayout *lPangoLayout = pango_layout_new(lPangoCtx); pango_layout_set_font_description(lPangoLayout, lPangoFontDescr); pango_layout_set_text(lPangoLayout, Sopra la panca la capra campa, strlen(Sopra la panca la capra campa)); cogl_pango_render_layout(lPangoLayout, mWidth/2, mHeight/2, lWhite, 0); cogl_path_ellipse(mWidth/2.0, mHeight/2.0, mWidth/4.0, mHeight/4.0); cogl_path_stroke(); cogl_color_free(lWhite); shows me the ellipse, but not the text. I get the message (testCOGL:13610): CoglPango-CRITICAL **: cogl_pango_get_renderer_from_context: assertion `COGL_PANGO_IS_FONT_MAP (font_map)' failed Any hints? Thanks O. -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
Re: [clutter] Using cogl without clutter
On Wed, 2010-04-07 at 16:16 +0200, Oscar Lazzarino wrote: OK, let's try lowering the bar ;-) Would it be possible to use cogl_pango outside of the clutter_text actor (i.e. in a custom actor)? yes. The cogl_pango functions are treated as private functions and not documented, as far as I can see, and the simple approach the fact that are undocumented has nothing to do with whether they are private or not. :-) private functions in clutter or cogl are prefixed by an underscore. CoglColor *lWhite = cogl_color_new(); cogl_color_set_from_4f(lWhite, 1.0, 1.0, 1.0, 1.0); don't allocate a new CoglColor - use it on the stack: CoglColor white; cogl_color_set_from_4f (white, 1.0, 1.0, 1.0, 1.0); cogl_set_source_color(lWhite); PangoContext *lPangoCtx = pango_context_new(); use: layout = clutter_actor_create_pango_layout (actor, some text); instead of creating the layout and context yourself. pango_font_description_set_family(lPangoFontDescr, Sans); pango_font_description_set_size(lPangoFontDescr, 10 * PANGO_SCALE); pango_layout_set_font_description(lPangoLayout, lPangoFontDescr); cogl_pango_render_layout(lPangoLayout, mWidth/2, mHeight/2, lWhite, 0); this should work. shows me the ellipse, but not the text. I get the message (testCOGL:13610): CoglPango-CRITICAL **: cogl_pango_get_renderer_from_context: assertion `COGL_PANGO_IS_FONT_MAP (font_map)' failed Any hints? yes: you should not use generic PangoCairo context and layouts, and use the ones that Clutter creates for you. :-) ciao, Emmanuele. -- Emmanuele Bassi, Open Source Software Engineer Intel Open Source Technology Center -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
Re: [clutter] Using cogl without clutter
On Wed, Apr 7, 2010 at 4:43 PM, Neil Roberts n...@linux.intel.com wrote: You can't call the cogl_pango_* functions using a layout created with a regular pango context - instead it has to be a context created with the special Cogl font map. The cogl_pango functions in cogl-pango.h are meant to be public so it is safe to use them. The lack of documentation is an oversight not an attempt to hide them. The usual way to paint custom text in an actor is to call clutter_actor_create_pango_layout() and then render it with cogl_pango_render_layout(). This will take advantage of the CoglPango glyph cache and render the text from textures so it should be relatively efficient. Hope that helps - Neil I did as you said, and it works :) Actually, just out of curiosity, I also tried to create the Pango context like this PangoFontMap *lPangoFontMap = cogl_pango_font_map_new(); PangoContext *lPangoCtx = pango_font_map_create_context(lPangoFontMap); and it also works. Thanks to everyone who answered :) O. -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
[clutter] Using cogl without clutter
Hi, would it be possibile to use cogl without clutter, on a gl context created with gtkglext? If so, a small example or some hints would be very useful. Thanks O. -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
Re: [clutter] Using cogl without clutter
On Tue, 2010-04-06 at 11:59 +0200, Oscar Lazzarino wrote: would it be possibile to use cogl without clutter, on a gl context created with gtkglext? no. ciao, Emmanuele. -- Emmanuele Bassi, Open Source Software Engineer Intel Open Source Technology Center -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
Re: [clutter] Using cogl without clutter
Excerpts from Oscar Lazzarino's message of Tue Apr 06 10:59:11 +0100 2010: Hi, would it be possibile to use cogl without clutter, on a gl context created with gtkglext? If so, a small example or some hints would be very useful. Hi, The long term goal is for Cogl to become a standalone 3D graphics API and we are incrementally working towards this goal. Cogl will also have a window system abstraction (only as far as framebuffer management is concerned, I don't mean anything relating input events etc) that could make it possible to integrate tightly with GTK in one way or another. Integrating with a GL context not owned by Cogl adds additional complexity but theoretically it would be possible to create a Cogl winsys that allowed this. Sorry that doesn't really help you, but you might be interested to know it may be possible one day. kind regards, - Robert Thanks O. -- Robert Bragg, Intel Open Source Technology Center -- To unsubscribe send a mail to clutter+unsubscr...@o-hand.com
