[mutter] cogl: Remove unused depth texture API

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 0e4c23c9851fc1b1228872dc4669d27ed9d259d7
Author: Adam Jackson <ajax redhat com>
Date:   Thu Oct 17 19:47:56 2019 -0400

    cogl: Remove unused depth texture API
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/866

 cogl/cogl/cogl-framebuffer-private.h      |  1 -
 cogl/cogl/cogl-framebuffer.c              | 35 -------------------
 cogl/cogl/cogl-framebuffer.h              | 56 -------------------------------
 cogl/cogl/cogl.symbols                    |  3 --
 cogl/cogl/driver/gl/cogl-framebuffer-gl.c | 32 ------------------
 5 files changed, 127 deletions(-)
---
diff --git a/cogl/cogl/cogl-framebuffer-private.h b/cogl/cogl/cogl-framebuffer-private.h
index e1a639411..30403e8a5 100644
--- a/cogl/cogl/cogl-framebuffer-private.h
+++ b/cogl/cogl/cogl-framebuffer-private.h
@@ -60,7 +60,6 @@ typedef struct
   CoglSwapChain *swap_chain;
   gboolean need_stencil;
   int samples_per_pixel;
-  gboolean depth_texture_enabled;
   gboolean stereo_enabled;
 } CoglFramebufferConfig;
 
diff --git a/cogl/cogl/cogl-framebuffer.c b/cogl/cogl/cogl-framebuffer.c
index 31a04f229..8164e5760 100644
--- a/cogl/cogl/cogl-framebuffer.c
+++ b/cogl/cogl/cogl-framebuffer.c
@@ -705,15 +705,6 @@ cogl_framebuffer_allocate (CoglFramebuffer *framebuffer,
 
   if (framebuffer->type == COGL_FRAMEBUFFER_TYPE_ONSCREEN)
     {
-      if (framebuffer->config.depth_texture_enabled)
-        {
-          g_set_error_literal (error, COGL_FRAMEBUFFER_ERROR,
-                               COGL_FRAMEBUFFER_ERROR_ALLOCATE,
-                               "Can't allocate onscreen framebuffer with a "
-                               "texture based depth buffer");
-          return FALSE;
-        }
-
       if (!winsys->onscreen_init (onscreen, error))
         return FALSE;
 
@@ -1049,32 +1040,6 @@ cogl_framebuffer_set_dither_enabled (CoglFramebuffer *framebuffer,
   framebuffer->dither_enabled = dither_enabled;
 }
 
-void
-cogl_framebuffer_set_depth_texture_enabled (CoglFramebuffer *framebuffer,
-                                            gboolean enabled)
-{
-  g_return_if_fail (!framebuffer->allocated);
-
-  framebuffer->config.depth_texture_enabled = enabled;
-}
-
-gboolean
-cogl_framebuffer_get_depth_texture_enabled (CoglFramebuffer *framebuffer)
-{
-  return framebuffer->config.depth_texture_enabled;
-}
-
-CoglTexture *
-cogl_framebuffer_get_depth_texture (CoglFramebuffer *framebuffer)
-{
-  /* lazily allocate the framebuffer... */
-  if (!cogl_framebuffer_allocate (framebuffer, NULL))
-    return NULL;
-
-  g_return_val_if_fail (cogl_is_offscreen (framebuffer), NULL);
-  return COGL_OFFSCREEN(framebuffer)->depth_texture;
-}
-
 int
 cogl_framebuffer_get_samples_per_pixel (CoglFramebuffer *framebuffer)
 {
diff --git a/cogl/cogl/cogl-framebuffer.h b/cogl/cogl/cogl-framebuffer.h
index 8fa313eea..b582dac71 100644
--- a/cogl/cogl/cogl-framebuffer.h
+++ b/cogl/cogl/cogl-framebuffer.h
@@ -837,62 +837,6 @@ void
 cogl_framebuffer_set_stereo_mode (CoglFramebuffer *framebuffer,
                                  CoglStereoMode stereo_mode);
 
-/**
- * cogl_framebuffer_set_depth_texture_enabled:
- * @framebuffer: A #CoglFramebuffer
- * @enabled: TRUE or FALSE
- *
- * If @enabled is #TRUE, the depth buffer used when rendering to @framebuffer
- * is available as a texture. You can retrieve the texture with
- * cogl_framebuffer_get_depth_texture().
- *
- * <note>It's not valid to call this function after the framebuffer has been
- * allocated as the creation of the depth texture is done at allocation time.
- * </note>
- *
- * Since: 1.14
- * Stability: unstable
- */
-void
-cogl_framebuffer_set_depth_texture_enabled (CoglFramebuffer *framebuffer,
-                                            gboolean enabled);
-
-/**
- * cogl_framebuffer_get_depth_texture_enabled:
- * @framebuffer: A #CoglFramebuffer
- *
- * Queries whether texture based depth buffer has been enabled via
- * cogl_framebuffer_set_depth_texture_enabled().
- *
- * Return value: %TRUE if a depth texture has been enabled, else
- *               %FALSE.
- *
- * Since: 1.14
- * Stability: unstable
- */
-gboolean
-cogl_framebuffer_get_depth_texture_enabled (CoglFramebuffer *framebuffer);
-
-/**
- * cogl_framebuffer_get_depth_texture:
- * @framebuffer: A #CoglFramebuffer
- *
- * Retrieves the depth buffer of @framebuffer as a #CoglTexture. You need to
- * call cogl_framebuffer_get_depth_texture(fb, TRUE); before using this
- * function.
- *
- * <note>Calling this function implicitely allocates the framebuffer.</note>
- * <note>The texture returned stays valid as long as the framebuffer stays
- * valid.</note>
- *
- * Returns: (transfer none): the depth texture
- *
- * Since: 1.14
- * Stability: unstable
- */
-CoglTexture *
-cogl_framebuffer_get_depth_texture (CoglFramebuffer *framebuffer);
-
 /**
  * cogl_framebuffer_set_samples_per_pixel:
  * @framebuffer: A #CoglFramebuffer framebuffer
diff --git a/cogl/cogl/cogl.symbols b/cogl/cogl/cogl.symbols
index 0710d626e..3a8fae384 100644
--- a/cogl/cogl/cogl.symbols
+++ b/cogl/cogl/cogl.symbols
@@ -230,8 +230,6 @@ cogl_framebuffer_get_blue_bits
 cogl_framebuffer_get_color_format
 cogl_framebuffer_get_context
 cogl_framebuffer_get_depth_bits
-cogl_framebuffer_get_depth_texture
-cogl_framebuffer_get_depth_texture_enabled
 cogl_framebuffer_get_depth_write_enabled
 cogl_framebuffer_get_dither_enabled
 cogl_framebuffer_get_green_bits
@@ -269,7 +267,6 @@ cogl_framebuffer_rotate_euler
 #endif
 
 cogl_framebuffer_scale
-cogl_framebuffer_set_depth_texture_enabled
 cogl_framebuffer_set_depth_write_enabled
 cogl_framebuffer_set_dither_enabled
 cogl_framebuffer_set_modelview_matrix
diff --git a/cogl/cogl/driver/gl/cogl-framebuffer-gl.c b/cogl/cogl/driver/gl/cogl-framebuffer-gl.c
index d9d9e5690..343793999 100644
--- a/cogl/cogl/driver/gl/cogl-framebuffer-gl.c
+++ b/cogl/cogl/driver/gl/cogl-framebuffer-gl.c
@@ -438,20 +438,6 @@ _cogl_framebuffer_gl_flush_state (CoglFramebuffer *draw_buffer,
   ctx->current_draw_buffer_changes &= ~state;
 }
 
-static CoglTexture *
-create_depth_texture (CoglContext *ctx,
-                      int width,
-                      int height)
-{
-  CoglTexture2D *depth_texture =
-    cogl_texture_2d_new_with_size (ctx, width, height);
-
-  cogl_texture_set_components (COGL_TEXTURE (depth_texture),
-                               COGL_TEXTURE_COMPONENTS_DEPTH);
-
-  return COGL_TEXTURE (depth_texture);
-}
-
 static CoglTexture *
 attach_depth_texture (CoglContext *ctx,
                       CoglTexture *depth_texture,
@@ -784,24 +770,6 @@ _cogl_offscreen_gl_allocate (CoglOffscreen *offscreen,
                                 &level_height,
                                 NULL);
 
-  if (fb->config.depth_texture_enabled &&
-      offscreen->depth_texture == NULL)
-    {
-      offscreen->depth_texture =
-        create_depth_texture (ctx,
-                              level_width,
-                              level_height);
-
-      if (!cogl_texture_allocate (offscreen->depth_texture, error))
-        {
-          cogl_object_unref (offscreen->depth_texture);
-          offscreen->depth_texture = NULL;
-          return FALSE;
-        }
-
-      _cogl_texture_associate_framebuffer (offscreen->depth_texture, fb);
-    }
-
   /* XXX: The framebuffer_object spec isn't clear in defining whether attaching
    * a texture as a renderbuffer with mipmap filtering enabled while the
    * mipmaps have not been uploaded should result in an incomplete framebuffer