[gtk/gamma-shenanigans] texture: Generalize download_16bit

[Matthias Clasen <matthiasc src gnome org>]

commit 94ff25c7ff73d1d4db2a5fb10fed6b91c858bc52
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Sep 6 19:48:47 2021 -0400

    texture: Generalize download_16bit
    
    Pass a format, so we can use this vfunc for both
    16bit and floating point formats.

 gdk/gdkgltexture.c      | 41 ++++++++++++++++++++++++++++++-----------
 gdk/gdkmemorytexture.c  |  7 ++++---
 gdk/gdktexture.c        | 12 +++++++-----
 gdk/gdktextureprivate.h |  7 +++++--
 4 files changed, 46 insertions(+), 21 deletions(-)
---
diff --git a/gdk/gdkgltexture.c b/gdk/gdkgltexture.c
index 974545f576..704b39cb17 100644
--- a/gdk/gdkgltexture.c
+++ b/gdk/gdkgltexture.c
@@ -112,12 +112,13 @@ gdk_gl_texture_download (GdkTexture         *texture,
 }
 
 static GBytes *
-gdk_gl_texture_download_16bit (GdkTexture *texture)
+gdk_gl_texture_download_format (GdkTexture      *texture,
+                                GdkMemoryFormat  format)
 {
   GdkGLTexture *self = GDK_GL_TEXTURE (texture);
   GdkSurface *surface;
   GdkGLContext *context;
-  int format = 0;
+  int internal_format = 0;
   gpointer data;
   gsize size;
 
@@ -126,18 +127,36 @@ gdk_gl_texture_download_16bit (GdkTexture *texture)
 
   gdk_gl_context_make_current (context);
   glBindTexture (GL_TEXTURE_2D, self->id);
-  glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, &format);
+  glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, &internal_format);
 
-  if (format != GL_RGBA16)
-    return NULL;
+  if (format == GDK_MEMORY_R16G16B16A16_PREMULTIPLIED)
+    {
+      if (format != GL_RGBA16)
+        return NULL;
+
+      size = texture->width * texture->height * 4 * sizeof (guint16);
+      data = malloc (size);
+
+      glReadPixels (0, 0, texture->width, texture->height,
+                    GL_RGBA16, GL_UNSIGNED_SHORT, data);
+
+      return g_bytes_new_take (data, size);
+    }
+  else if (format == GDK_MEMORY_R32G32B32_FLOAT)
+    {
+      if (format != GL_RGB32F)
+        return NULL;
 
-  size = texture->width * texture->height * 4 * sizeof (guint16);
-  data = malloc (size);
+      size = texture->width * texture->height * 3 * sizeof (float);
+      data = malloc (size);
 
-  glReadPixels (0, 0, texture->width, texture->height,
-                GL_RGBA16, GL_UNSIGNED_SHORT, data);
+      glReadPixels (0, 0, texture->width, texture->height,
+                    GL_RGBA32F, GL_FLOAT, data);
 
-  return g_bytes_new_take (data, size);
+      return g_bytes_new_take (data, size);
+    }
+  else
+    return NULL;
 }
 
 static void
@@ -147,7 +166,7 @@ gdk_gl_texture_class_init (GdkGLTextureClass *klass)
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 
   texture_class->download = gdk_gl_texture_download;
-  texture_class->download_16bit = gdk_gl_texture_download_16bit;
+  texture_class->download_format = gdk_gl_texture_download_format;
   gobject_class->dispose = gdk_gl_texture_dispose;
 }
 
diff --git a/gdk/gdkmemorytexture.c b/gdk/gdkmemorytexture.c
index b2bdd1d50e..dd112dfb30 100644
--- a/gdk/gdkmemorytexture.c
+++ b/gdk/gdkmemorytexture.c
@@ -108,11 +108,12 @@ gdk_memory_texture_download (GdkTexture         *texture,
 }
 
 static GBytes *
-gdk_memory_texture_download_16bit (GdkTexture *texture)
+gdk_memory_texture_download_format (GdkTexture      *texture,
+                                    GdkMemoryFormat  format)
 {
   GdkMemoryTexture *self = GDK_MEMORY_TEXTURE (texture);
 
-  if (self->format == GDK_MEMORY_R16G16B16A16_PREMULTIPLIED)
+  if (self->format == format)
     return g_bytes_ref (self->bytes);
 
   return NULL;
@@ -125,7 +126,7 @@ gdk_memory_texture_class_init (GdkMemoryTextureClass *klass)
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 
   texture_class->download = gdk_memory_texture_download;
-  texture_class->download_16bit = gdk_memory_texture_download_16bit;
+  texture_class->download_format = gdk_memory_texture_download_format;
   gobject_class->dispose = gdk_memory_texture_dispose;
 }
 
diff --git a/gdk/gdktexture.c b/gdk/gdktexture.c
index e158b62068..d12c5af02b 100644
--- a/gdk/gdktexture.c
+++ b/gdk/gdktexture.c
@@ -126,7 +126,8 @@ gdk_texture_real_download (GdkTexture         *self,
 }
 
 static GBytes *
-gdk_texture_real_download_16bit (GdkTexture *self)
+gdk_texture_real_download_format (GdkTexture      *self,
+                                  GdkMemoryFormat  format)
 {
   return NULL;
 }
@@ -195,7 +196,7 @@ gdk_texture_class_init (GdkTextureClass *klass)
   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 
   klass->download = gdk_texture_real_download;
-  klass->download_16bit = gdk_texture_real_download_16bit;
+  klass->download_format = gdk_texture_real_download_format;
 
   gobject_class->set_property = gdk_texture_set_property;
   gobject_class->get_property = gdk_texture_get_property;
@@ -572,9 +573,10 @@ gdk_texture_download (GdkTexture *texture,
 }
 
 GBytes *
-gdk_texture_download_16bit (GdkTexture *texture)
+gdk_texture_download_format (GdkTexture      *texture,
+                             GdkMemoryFormat  format)
 {
-  return GDK_TEXTURE_GET_CLASS (texture)->download_16bit (texture);
+  return GDK_TEXTURE_GET_CLASS (texture)->download_format (texture, format);
 }
 
 gboolean
@@ -647,7 +649,7 @@ gdk_texture_save_to_png (GdkTexture *texture,
   image.width = gdk_texture_get_width (texture);
   image.height = gdk_texture_get_height (texture);
 
-  bytes = gdk_texture_download_16bit (texture);
+  bytes = gdk_texture_download_format (texture, GDK_MEMORY_R16G16B16A16_PREMULTIPLIED);
   if (bytes)
     {
       image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
diff --git a/gdk/gdktextureprivate.h b/gdk/gdktextureprivate.h
index e0b7b842a6..f00d712d08 100644
--- a/gdk/gdktextureprivate.h
+++ b/gdk/gdktextureprivate.h
@@ -2,6 +2,7 @@
 #define __GDK_TEXTURE_PRIVATE_H__
 
 #include "gdktexture.h"
+#include "gdkmemorytexture.h"
 
 G_BEGIN_DECLS
 
@@ -28,7 +29,8 @@ struct _GdkTextureClass {
                                                          const GdkRectangle     *area,
                                                          guchar                 *data,
                                                          gsize                   stride);
-  GBytes *              (* download_16bit)              (GdkTexture             *texture);
+  GBytes *              (* download_format)             (GdkTexture             *texture,
+                                                         GdkMemoryFormat         format);
 };
 
 gpointer                gdk_texture_new                 (const GdkTextureClass  *klass,
@@ -49,7 +51,8 @@ void                    gdk_texture_clear_render_data   (GdkTexture
 gpointer                gdk_texture_get_render_data     (GdkTexture             *self,
                                                          gpointer                key);
 
-GBytes *                gdk_texture_download_16bit      (GdkTexture             *texture);
+GBytes *                gdk_texture_download_format     (GdkTexture             *texture,
+                                                         GdkMemoryFormat         format);
 
 G_END_DECLS