[gimp/gimp-2-10] file-dds: support for DXT2/DXT4, initial build and GEGL-related fixes

[Jehan <jehanp src gnome org>]

commit 994368d68d8942f65553add40bebcebbc8c55c9e
Author: Massimo Valentini <mvalentini src gnome org>
Date:   Tue Nov 13 02:44:11 2018 +0300

    file-dds: support for DXT2/DXT4, initial build and GEGL-related fixes
    
    (cherry picked from commit d25348ca2473a2efe26824b41daa32319e349e7e)

 plug-ins/file-dds/color.c   |  1 +
 plug-ins/file-dds/ddsread.c | 26 ++++++++++++++++++++++----
 plug-ins/file-dds/mipmap.c  |  4 ++--
 plug-ins/file-dds/misc.c    | 13 +++++++------
 4 files changed, 32 insertions(+), 12 deletions(-)
---
diff --git a/plug-ins/file-dds/color.c b/plug-ins/file-dds/color.c
index edc8f6c93e..3ec0f17a01 100644
--- a/plug-ins/file-dds/color.c
+++ b/plug-ins/file-dds/color.c
@@ -21,6 +21,7 @@
 */
 
 #include <math.h>
+#include "color.h"
 
 int linear_to_sRGB(int c)
 {
diff --git a/plug-ins/file-dds/ddsread.c b/plug-ins/file-dds/ddsread.c
index c2af3d50b2..97ee510a34 100644
--- a/plug-ins/file-dds/ddsread.c
+++ b/plug-ins/file-dds/ddsread.c
@@ -440,6 +440,7 @@ GimpPDBStatusType read_dds(gchar *filename, gint32 *imageID)
    }
 
    gimp_image_set_active_layer(image, layers[0]);
+   g_free (layers);
 
    *imageID = image;
 
@@ -541,7 +542,9 @@ static int validate_header(dds_header_t *hdr)
 
    if((hdr->pixelfmt.flags & DDPF_FOURCC) &&
       fourcc != FOURCC('D','X','T','1') &&
+      fourcc != FOURCC('D','X','T','2') &&
       fourcc != FOURCC('D','X','T','3') &&
+      fourcc != FOURCC('D','X','T','4') &&
       fourcc != FOURCC('D','X','T','5') &&
       fourcc != FOURCC('R','X','G','B') &&
       fourcc != FOURCC('A','T','I','1') &&
@@ -597,7 +600,9 @@ static int validate_header(dds_header_t *hdr)
       switch(fourcc)
       {
          case FOURCC('D','X','T','1'):
+         case FOURCC('D','X','T','2'):
          case FOURCC('D','X','T','3'):
+         case FOURCC('D','X','T','4'):
          case FOURCC('D','X','T','5'):
          case FOURCC('R','X','G','B'):
          case FOURCC('A','T','I','1'):
@@ -796,6 +801,17 @@ static int setup_dxgi_format(dds_header_t *hdr, dds_header_dx10_t *dx10hdr)
    return(1);
 }
 
+
+static const Babl*
+premultiplied_variant (const Babl* format)
+{
+  if (format == babl_format ("R'G'B'A u8"))
+    return babl_format ("R'aG'aB'aA u8");
+  else
+    g_printerr ("Add format %s to premultiplied_variant() %s: %d\n", babl_get_name (format), __FILE__, 
__LINE__);
+  return format;
+}
+
 static int load_layer(FILE *fp, dds_header_t *hdr, dds_load_info_t *d,
                       gint32 image, unsigned int level, char *prefix,
                       unsigned int *l, guchar *pixels, unsigned char *buf)
@@ -888,7 +904,9 @@ static int load_layer(FILE *fp, dds_header_t *hdr, dds_load_info_t *d,
       switch(GETL32(hdr->pixelfmt.fourcc))
       {
          case FOURCC('D','X','T','1'): format = DDS_COMPRESS_BC1; break;
+         case FOURCC('D','X','T','2'): bablfmt = premultiplied_variant (bablfmt);
          case FOURCC('D','X','T','3'): format = DDS_COMPRESS_BC2; break;
+         case FOURCC('D','X','T','4'): bablfmt = premultiplied_variant (bablfmt);
          case FOURCC('D','X','T','5'): format = DDS_COMPRESS_BC3; break;
          case FOURCC('R','X','G','B'): format = DDS_COMPRESS_BC3; break;
          case FOURCC('A','T','I','1'):
@@ -920,7 +938,7 @@ static int load_layer(FILE *fp, dds_header_t *hdr, dds_load_info_t *d,
       {
          if(n >= d->tile_height)
          {
-            gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 1.0,
+            gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 0,
                             bablfmt, pixels, GEGL_AUTO_ROWSTRIDE);
             n = 0;
             gimp_progress_update((double)y / (double)hdr->height);
@@ -1036,7 +1054,7 @@ static int load_layer(FILE *fp, dds_header_t *hdr, dds_load_info_t *d,
          }
       }
 
-      gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 1.0,
+      gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 0,
                       bablfmt, pixels, GEGL_AUTO_ROWSTRIDE);
    }
    else if(hdr->pixelfmt.flags & DDPF_FOURCC)
@@ -1067,7 +1085,7 @@ static int load_layer(FILE *fp, dds_header_t *hdr, dds_load_info_t *d,
       {
          if(n >= d->tile_height)
          {
-            gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 1.0,
+            gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 0,
                             bablfmt, pixels, GEGL_AUTO_ROWSTRIDE);
             n = 0;
             gimp_progress_update((double)y / (double)hdr->height);
@@ -1078,7 +1096,7 @@ static int load_layer(FILE *fp, dds_header_t *hdr, dds_load_info_t *d,
                 width * d->gimp_bpp);
       }
 
-      gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 1.0,
+      gegl_buffer_set(buffer, GEGL_RECTANGLE(0, y - n, layerw, n), 0,
                       bablfmt, pixels, GEGL_AUTO_ROWSTRIDE);
       
       g_free(dst);
diff --git a/plug-ins/file-dds/mipmap.c b/plug-ins/file-dds/mipmap.c
index 71b58d84e5..34f2d66283 100644
--- a/plug-ins/file-dds/mipmap.c
+++ b/plug-ins/file-dds/mipmap.c
@@ -765,7 +765,7 @@ static struct
  *   if (texel_alpha < alpha_test_threshold)
  *      discard;
  */
-float calc_alpha_test_coverage(unsigned char *src,
+static float calc_alpha_test_coverage(unsigned char *src,
                                unsigned int width, unsigned int height, int bpp,
                                float alpha_test_threshold,
                                float alpha_scale)
@@ -796,7 +796,7 @@ float calc_alpha_test_coverage(unsigned char *src,
    return (float)coverage / (width * height);
 }
 
-void scale_alpha_to_coverage(unsigned char *img,
+static void scale_alpha_to_coverage(unsigned char *img,
                              unsigned int width, unsigned int height, int bpp,
                              float desired_coverage,
                              float alpha_test_threshold)
diff --git a/plug-ins/file-dds/misc.c b/plug-ins/file-dds/misc.c
index 4183c27191..1a09031a32 100644
--- a/plug-ins/file-dds/misc.c
+++ b/plug-ins/file-dds/misc.c
@@ -21,6 +21,7 @@
 */
 
 #include <libgimp/gimp.h>
+#include "misc.h"
 
 static inline float saturate(float a)
 {
@@ -44,7 +45,7 @@ void decode_ycocg_image(gint32 drawableID, gboolean shadow)
    if(shadow)
    {
       sbuffer = gimp_drawable_get_shadow_buffer(drawableID);
-      gegl_buffer_copy(buffer, NULL, sbuffer, NULL);
+      gegl_buffer_copy(buffer, NULL, GEGL_ABYSS_NONE, sbuffer, NULL);
       g_object_unref(buffer);
       buffer = sbuffer;
    }
@@ -87,7 +88,7 @@ void decode_ycocg_image(gint32 drawableID, gboolean shadow)
          gimp_progress_update((float)i / (float)num_pixels);
    }
 
-   gegl_buffer_set(buffer, GEGL_RECTANGLE(0, 0, w, h), 1.0, format, data,
+   gegl_buffer_set(buffer, GEGL_RECTANGLE(0, 0, w, h), 0, format, data,
                    GEGL_AUTO_ROWSTRIDE);
 
    gimp_progress_update(1.0);
@@ -119,7 +120,7 @@ void decode_ycocg_scaled_image(gint32 drawableID, gboolean shadow)
    if(shadow)
    {
       sbuffer = gimp_drawable_get_shadow_buffer(drawableID);
-      gegl_buffer_copy(buffer, NULL, sbuffer, NULL);
+      gegl_buffer_copy(buffer, NULL, GEGL_ABYSS_NONE, sbuffer, NULL);
       g_object_unref(buffer);
       buffer = sbuffer;
    }
@@ -165,7 +166,7 @@ void decode_ycocg_scaled_image(gint32 drawableID, gboolean shadow)
          gimp_progress_update((float)i / (float)num_pixels);
    }
 
-   gegl_buffer_set(buffer, GEGL_RECTANGLE(0, 0, w, h), 1.0, format, data,
+   gegl_buffer_set(buffer, GEGL_RECTANGLE(0, 0, w, h), 0, format, data,
                    GEGL_AUTO_ROWSTRIDE);
    
    gimp_progress_update(1.0);
@@ -195,7 +196,7 @@ void decode_alpha_exp_image(gint32 drawableID, gboolean shadow)
    if(shadow)
    {
       sbuffer = gimp_drawable_get_shadow_buffer(drawableID);
-      gegl_buffer_copy(buffer, NULL, sbuffer, NULL);
+      gegl_buffer_copy(buffer, NULL, GEGL_ABYSS_NONE, sbuffer, NULL);
       g_object_unref(buffer);
       buffer = sbuffer;
    }
@@ -234,7 +235,7 @@ void decode_alpha_exp_image(gint32 drawableID, gboolean shadow)
          gimp_progress_update((float)i / (float)num_pixels);
    }
 
-   gegl_buffer_set(buffer, GEGL_RECTANGLE(0, 0, w, h), 1.0, format, data,
+   gegl_buffer_set(buffer, GEGL_RECTANGLE(0, 0, w, h), 0, format, data,
                    GEGL_AUTO_ROWSTRIDE);
    
    gimp_progress_update(1.0);