Mesa (master): meta: Support GenerateMipmaps on 1DArray textures.

[Kenneth Graunke]

Module: Mesa
Branch: master
Commit: 14ca611258d8737cb79f9f5f2e0aaf58d80a1b1c
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=14ca611258d8737cb79f9f5f2e0aaf58d80a1b1c

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Thu Mar  6 01:56:53 2014 -0800

meta: Support GenerateMipmaps on 1DArray textures.

I don't know how many people care about this case, but it's easy enough
to do, so we may as well.  The tricky part is that for some reason Mesa
stores the number of array slices in Height, not Depth.

I thought the easiest way to handle that here was to make Height = 1
(the actual height), and srcDepth = srcImage->Height.  This requires
some munging when calling _mesa_prepare_mipmap_level, so I created a
wrapper that sorts it out for us.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
Reviewed-by: Matt Turner <mattst88 at gmail.com>
Reviewed-by: Anuj Phogat <anuj.phogat at gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

---

 src/mesa/drivers/common/meta_generate_mipmap.c |   42 +++++++++++++++++++-----
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/src/mesa/drivers/common/meta_generate_mipmap.c b/src/mesa/drivers/common/meta_generate_mipmap.c
index 9d352e9..3db073a 100644
--- a/src/mesa/drivers/common/meta_generate_mipmap.c
+++ b/src/mesa/drivers/common/meta_generate_mipmap.c
@@ -94,7 +94,7 @@ fallback_required(struct gl_context *ctx, GLenum target,
    GLenum status;
 
    /* check for fallbacks */
-   if (target == GL_TEXTURE_3D || target == GL_TEXTURE_1D_ARRAY) {
+   if (target == GL_TEXTURE_3D) {
       _mesa_perf_debug(ctx, MESA_DEBUG_SEVERITY_HIGH,
                        "glGenerateMipmap() to %s target\n",
                        _mesa_lookup_enum_by_nr(target));
@@ -163,6 +163,22 @@ _mesa_meta_glsl_generate_mipmap_cleanup(struct gen_mipmap_state *mipmap)
    _mesa_meta_blit_shader_table_cleanup(&mipmap->shaders);
 }
 
+static GLboolean
+prepare_mipmap_level(struct gl_context *ctx,
+                     struct gl_texture_object *texObj, GLuint level,
+                     GLsizei width, GLsizei height, GLsizei depth,
+                     GLenum intFormat, mesa_format format)
+{
+   if (texObj->Target == GL_TEXTURE_1D_ARRAY) {
+      /* Work around Mesa expecting the number of array slices in "height". */
+      height = depth;
+      depth = 1;
+   }
+
+   return _mesa_prepare_mipmap_level(ctx, texObj, level, width, height, depth,
+                                     0, intFormat, format);
+}
+
 /**
  * Called via ctx->Driver.GenerateMipmap()
  * Note: We don't yet support 3D textures, 1D/2D array textures or texture
@@ -276,8 +292,13 @@ _mesa_meta_GenerateMipmap(struct gl_context *ctx, GLenum target,
 
       /* src size */
       srcWidth = srcImage->Width;
-      srcHeight = srcImage->Height;
-      srcDepth = srcImage->Depth;
+      if (target == GL_TEXTURE_1D_ARRAY) {
+         srcHeight = 1;
+         srcDepth = srcImage->Height;
+      } else {
+         srcHeight = srcImage->Height;
+         srcDepth = srcImage->Depth;
+      }
 
       /* new dst size */
       dstWidth = minify(srcWidth, 1);
@@ -296,11 +317,10 @@ _mesa_meta_GenerateMipmap(struct gl_context *ctx, GLenum target,
       /* Set MaxLevel large enough to hold the new level when we allocate it */
       _mesa_TexParameteri(target, GL_TEXTURE_MAX_LEVEL, dstLevel);
 
-      if (!_mesa_prepare_mipmap_level(ctx, texObj, dstLevel,
-                                      dstWidth, dstHeight, dstDepth,
-                                      srcImage->Border,
-                                      srcImage->InternalFormat,
-                                      srcImage->TexFormat)) {
+      if (!prepare_mipmap_level(ctx, texObj, dstLevel,
+                                dstWidth, dstHeight, dstDepth,
+                                srcImage->InternalFormat,
+                                srcImage->TexFormat)) {
          /* All done.  We either ran out of memory or we would go beyond the
           * last valid level of an immutable texture if we continued.
           */
@@ -339,7 +359,11 @@ _mesa_meta_GenerateMipmap(struct gl_context *ctx, GLenum target,
          }
 
          assert(dstWidth == ctx->DrawBuffer->Width);
-         assert(dstHeight == ctx->DrawBuffer->Height);
+         if (target == GL_TEXTURE_1D_ARRAY) {
+            assert(dstHeight == 1);
+         } else {
+            assert(dstHeight == ctx->DrawBuffer->Height);
+         }
 
          _mesa_DrawArrays(GL_TRIANGLE_FAN, 0, 4);
       }