[Mesa-dev] [PATCH 1/2] mesa: new _mesa_prepare_mipmap_levels() function for mipmap generation

[Ian Romanick]

On 03/26/2016 10:21 AM, Brian Paul wrote:
> Simplifies the loops in generate_mipmap_uncompressed() and
> generate_mipmap_compressed().  Will be used in the state tracker too.
> Could probably be used in the meta code.  If so, some additional
> clean-ups can be done after that.

I'm in favor of just about anything that can lead to clean ups in meta.
 I have a couple comments below.

> ---
>  src/mesa/main/mipmap.c | 89 ++++++++++++++++++++++++++++++++------------------
>  src/mesa/main/mipmap.h |  5 +++
>  2 files changed, 63 insertions(+), 31 deletions(-)
> 
> diff --git a/src/mesa/main/mipmap.c b/src/mesa/main/mipmap.c
> index 5a02780..02d236d 100644
> --- a/src/mesa/main/mipmap.c
> +++ b/src/mesa/main/mipmap.c
> @@ -1872,6 +1872,50 @@ _mesa_prepare_mipmap_level(struct gl_context *ctx,
>  }
>  
>  
> +/**
> + * Prepare all mipmap levels beyond 'baseLevel' for mipmap generation.
> + * When finished, all the gl_texture_image structures for the smaller
> + * mipmap levels will be consistent with the base level (in terms of
> + * dimensions, format, etc).
> + */
> +void
> +_mesa_prepare_mipmap_levels(struct gl_context *ctx,
> +                            struct gl_texture_object *texObj,
> +                            GLuint baseLevel, GLuint maxLevel)

Can these be plain unsigned?

> +{
> +   const struct gl_texture_image *baseImage =
> +      _mesa_select_tex_image(texObj, texObj->Target, baseLevel);
> +   const GLint border = 0;
> +   GLint width = baseImage->Width;
> +   GLint height = baseImage->Height;
> +   GLint depth = baseImage->Depth;
> +   const GLenum intFormat = baseImage->InternalFormat;
> +   const mesa_format texFormat = baseImage->TexFormat;
> +   GLint newWidth, newHeight, newDepth;
> +   GLuint level;
> +
> +   /* Prepare baseLevel + 1, baseLevel + 2, ... */
> +   for (level = baseLevel + 1; level <= maxLevel; level++) {

Now that we can use more C99, I'm in favor of

   for (unsigned level = baseLevel + 1; level <= maxLevel; level++) {

> +      if (!_mesa_next_mipmap_level_size(texObj->Target, border,
> +                                        width, height, depth,
> +                                        &newWidth, &newHeight, &newDepth)) {

Meta has some special handling for GL_TEXTURE_1D_ARRAY. I think that
needs to be done here too.

> +         /* all done */
> +         break;
> +      }
> +
> +      if (!_mesa_prepare_mipmap_level(ctx, texObj, level,
> +                                      newWidth, newHeight, newDepth,
> +                                      border, intFormat, texFormat)) {
> +         break;
> +      }
> +
> +      width = newWidth;
> +      height = newHeight;
> +      depth = newDepth;
> +   }
> +}
> +
> +
>  static void
>  generate_mipmap_uncompressed(struct gl_context *ctx, GLenum target,
>  			     struct gl_texture_object *texObj,
> @@ -1892,7 +1936,6 @@ generate_mipmap_uncompressed(struct gl_context *ctx, GLenum target,
>        GLint dstWidth, dstHeight, dstDepth;
>        GLint border;
>        GLint slice;
> -      GLboolean nextLevel;
>        GLubyte **srcMaps, **dstMaps;
>        GLboolean success = GL_TRUE;
>  
> @@ -1904,22 +1947,14 @@ generate_mipmap_uncompressed(struct gl_context *ctx, GLenum target,
>        srcDepth = srcImage->Depth;
>        border = srcImage->Border;
>  
> -      nextLevel = _mesa_next_mipmap_level_size(target, border,
> -                                         srcWidth, srcHeight, srcDepth,
> -                                         &dstWidth, &dstHeight, &dstDepth);
> -      if (!nextLevel)
> -         return;
> -
> -      if (!_mesa_prepare_mipmap_level(ctx, texObj, level + 1,
> -                                      dstWidth, dstHeight, dstDepth,
> -                                      border, srcImage->InternalFormat,
> -                                      srcImage->TexFormat)) {
> -         return;
> -      }
> -
>        /* get dest gl_texture_image */
>        dstImage = _mesa_select_tex_image(texObj, target, level + 1);
> -      assert(dstImage);
> +      if (!dstImage) {
> +         break;
> +      }
> +      dstWidth = dstImage->Width;
> +      dstHeight = dstImage->Height;
> +      dstDepth = dstImage->Depth;
>  
>        if (target == GL_TEXTURE_1D_ARRAY) {
>  	 srcDepth = srcHeight;
> @@ -2087,7 +2122,6 @@ generate_mipmap_compressed(struct gl_context *ctx, GLenum target,
>        GLint srcWidth, srcHeight, srcDepth;
>        GLint dstWidth, dstHeight, dstDepth;
>        GLint border;
> -      GLboolean nextLevel;
>        GLuint temp_dst_row_stride, temp_dst_img_stride; /* in bytes */
>        GLint i;
>  
> @@ -2099,23 +2133,14 @@ generate_mipmap_compressed(struct gl_context *ctx, GLenum target,
>        srcDepth = srcImage->Depth;
>        border = srcImage->Border;
>  
> -      nextLevel = _mesa_next_mipmap_level_size(target, border,
> -                                         srcWidth, srcHeight, srcDepth,
> -                                         &dstWidth, &dstHeight, &dstDepth);
> -      if (!nextLevel)
> -	 goto end;
> -
> -      if (!_mesa_prepare_mipmap_level(ctx, texObj, level + 1,
> -                                      dstWidth, dstHeight, dstDepth,
> -                                      border, srcImage->InternalFormat,
> -                                      srcImage->TexFormat)) {
> -         /* all done */
> -         goto end;
> -      }
> -
>        /* get dest gl_texture_image */
>        dstImage = _mesa_select_tex_image(texObj, target, level + 1);
> -      assert(dstImage);
> +      if (!dstImage) {
> +         break;
> +      }
> +      dstWidth = dstImage->Width;
> +      dstHeight = dstImage->Height;
> +      dstDepth = dstImage->Depth;
>  
>        /* Compute dst image strides and alloc memory on first iteration */
>        temp_dst_row_stride = _mesa_format_row_stride(temp_format, dstWidth);
> @@ -2194,6 +2219,8 @@ _mesa_generate_mipmap(struct gl_context *ctx, GLenum target,
>  
>     maxLevel = MIN2(maxLevel, texObj->MaxLevel);
>  
> +   _mesa_prepare_mipmap_levels(ctx, texObj, texObj->BaseLevel, maxLevel);
> +
>     if (_mesa_is_format_compressed(srcImage->TexFormat)) {
>        generate_mipmap_compressed(ctx, target, texObj, srcImage, maxLevel);
>     } else {
> diff --git a/src/mesa/main/mipmap.h b/src/mesa/main/mipmap.h
> index c0366d3..0ed7934 100644
> --- a/src/mesa/main/mipmap.h
> +++ b/src/mesa/main/mipmap.h
> @@ -47,6 +47,11 @@ _mesa_prepare_mipmap_level(struct gl_context *ctx,
>                             GLsizei width, GLsizei height, GLsizei depth,
>                             GLsizei border, GLenum intFormat, mesa_format format);
>  
> +void
> +_mesa_prepare_mipmap_levels(struct gl_context *ctx,
> +                            struct gl_texture_object *texObj,
> +                            GLuint baseLevel, GLuint maxLevel);
> +
>  extern void
>  _mesa_generate_mipmap(struct gl_context *ctx, GLenum target,
>                        struct gl_texture_object *texObj);
>