Function

Gdk-4.0 ▶ Gdk ▶ cairo_draw_from_glDeprecated 4.6

  • Draws GL content onto a cairo context.

    It takes a render buffer ID (source_type == GL_RENDERBUFFER) or a texture id (source_type == GL_TEXTURE) and draws it onto cr with an OVER operation, respecting the current clip. The top left corner of the rectangle specified by x, y, width and height will be drawn at the current (0,0) position of the cairo_t.

    This will work for all cairo_t, as long as surface is realized, but the fallback implementation that reads back the pixels from the buffer may be used in the general case. In the case of direct drawing to a surface with no special effects applied to cr it will however use a more efficient approach.

    For GL_RENDERBUFFER the code will always fall back to software for buffers with alpha components, so make sure you use GL_TEXTURE if using alpha.

    Calling this may change the current GL context.

    Parameters

    • Deprecatedcr: default.Context

      a cairo context

    • Deprecatedsurface: Gdk.Surface

      The surface we're rendering for (not necessarily into)

    • Deprecatedsource: number

      The GL ID of the source buffer

    • Deprecatedsource_type: number

      The type of the source

    • Deprecatedbuffer_scale: number

      The scale-factor that the source buffer is allocated for

    • Deprecatedx: number

      The source x position in source to start copying from in GL coordinates

    • Deprecatedy: number

      The source y position in source to start copying from in GL coordinates

    • Deprecatedwidth: number

      The width of the region to draw

    • Deprecatedheight: number

      The height of the region to draw

    Returns void

    since 4.6: The function is overly complex and produces broken output in various combinations of arguments. If you want to draw with GL textures in GTK, use Gdk.GLTexture.new; if you want to use that texture in Cairo, use Gdk.Texture.download to download the data into a Cairo image surface.