[retro-gtk: 10/12] gl-display: Add load_texture() method

[Adrien Plazas <aplazas src gnome org>]

commit f2faf29228136ab0d1731f99c90e7fc03c048793
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Sat Nov 18 10:17:12 2017 +0100

    gl-display: Add load_texture() method
    
    This helps decoupling loading the texture from the rendering method.

 retro-gtk/retro-gl-display.c |   37 ++++++++++++++++++++++++-------------
 retro-gtk/retro-pixdata.c    |   31 ++++++++++++++++++++++++++++++-
 2 files changed, 54 insertions(+), 14 deletions(-)
---
diff --git a/retro-gtk/retro-gl-display.c b/retro-gtk/retro-gl-display.c
index c6bfc19..39061f9 100644
--- a/retro-gtk/retro-gl-display.c
+++ b/retro-gtk/retro-gl-display.c
@@ -91,6 +91,29 @@ retro_gl_display_get_video_box (RetroGLDisplay *self,
   *y = (h - *height) / 2;
 }
 
+static gboolean
+retro_gl_display_load_texture (RetroGLDisplay *self,
+                               gint           *texture_width,
+                               gint           *texture_height)
+{
+  if (retro_gl_display_get_pixbuf (self) == NULL)
+    return FALSE;
+
+  *texture_width = gdk_pixbuf_get_width (self->pixbuf),
+  *texture_height = gdk_pixbuf_get_height (self->pixbuf),
+
+  glTexImage2D (GL_TEXTURE_2D,
+                0,
+                GL_RGB,
+                *texture_width,
+                *texture_height,
+                0,
+                GL_RGBA, GL_UNSIGNED_BYTE,
+                gdk_pixbuf_get_pixels (self->pixbuf));
+
+  return TRUE;
+}
+
 static void
 retro_gl_display_blit_texture (RetroGLDisplay *self,
                                GLenum          filter,
@@ -262,21 +285,9 @@ retro_gl_display_render (RetroGLDisplay *self)
     RETRO_VIDEO_FILTER_SMOOTH :
     self->filter;
 
-  if (self->pixbuf == NULL)
+  if (!retro_gl_display_load_texture (self, &texture_width, &texture_height))
     return FALSE;
 
-  texture_width = gdk_pixbuf_get_width (self->pixbuf);
-  texture_height = gdk_pixbuf_get_height (self->pixbuf);
-
-  glTexImage2D (GL_TEXTURE_2D,
-                0,
-                GL_RGB,
-                texture_width,
-                texture_height,
-                0,
-                GL_RGBA, GL_UNSIGNED_BYTE,
-                gdk_pixbuf_get_pixels (self->pixbuf));
-
   if (filter == RETRO_VIDEO_FILTER_SMOOTH) {
     retro_gl_display_blit_texture (self, GL_LINEAR, texture_width, texture_height);
 
diff --git a/retro-gtk/retro-pixdata.c b/retro-gtk/retro-pixdata.c
index 87c2b06..b46c7fa 100644
--- a/retro-gtk/retro-pixdata.c
+++ b/retro-gtk/retro-pixdata.c
@@ -365,16 +365,45 @@ retro_pixdata_to_pixbuf (RetroPixdata *self)
 gboolean
 retro_pixdata_load_gl_texture (RetroPixdata *self)
 {
+  GLenum format;
+  GLenum type;
+  gint pixel_size;
+
   g_return_val_if_fail (self != NULL, FALSE);
 
+  switch (self->pixel_format) {
+  case RETRO_PIXEL_FORMAT_XRGB1555:
+    format = GL_BGRA;
+    type =  GL_UNSIGNED_SHORT_5_5_5_1;
+    pixel_size = 2;
+
+    break;
+  case RETRO_PIXEL_FORMAT_XRGB8888:
+    format = GL_BGRA;
+    type = GL_UNSIGNED_BYTE;
+    pixel_size = 4;
+
+    break;
+  case RETRO_PIXEL_FORMAT_RGB565:
+    format = GL_RGB;
+    type =  GL_UNSIGNED_SHORT_5_6_5;
+    pixel_size = 2;
+
+    break;
+  default:
+    return FALSE;
+  }
+
+  glPixelStorei (GL_UNPACK_ROW_LENGTH, self->rowstride / pixel_size);
   glTexImage2D (GL_TEXTURE_2D,
                 0,
                 GL_RGB,
                 self->width,
                 self->height,
                 0,
-                GL_BGRA, GL_UNSIGNED_BYTE,
+                format, type,
                 self->data);
+  glPixelStorei (GL_UNPACK_ROW_LENGTH, 0);
 
   return TRUE;
 }