mesa: finish implementing ARB_texture_stencil8 (v5)

Parts of this were implemented previously, so finish it off.

v2: fix getteximage falling into the integer check
    add fixes for the FBO paths, (fbo-stencil8 test).

v3: fix getteximage path harder.
v4: remove swapbytes from getteximage path (Ilia)
v5: brown paper bag the swapbytes removal. (Ilia)

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Dave Airlie <airlied@redhat.com>

4 files changed, 58 insertions, 5 deletions

diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index 861b15006f..3d4965cc30 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -186,6 +186,7 @@ static const struct extension extension_table[] = {
    { "GL_ARB_texture_rectangle",                   o(NV_texture_rectangle),                    GL,             2004 },
    { "GL_ARB_texture_rgb10_a2ui",                  o(ARB_texture_rgb10_a2ui),                  GL,             2009 },
    { "GL_ARB_texture_rg",                          o(ARB_texture_rg),                          GL,             2008 },
+   { "GL_ARB_texture_stencil8",                    o(ARB_texture_stencil8),                    GL,             2013 },
    { "GL_ARB_texture_storage",                     o(dummy_true),                              GL,             2011 },
    { "GL_ARB_texture_storage_multisample",         o(ARB_texture_multisample),                 GL,             2012 },
    { "GL_ARB_texture_view",                        o(ARB_texture_view),                        GL,             2012 },
diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index 8032585abd..27cf97f177 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -813,8 +813,10 @@ test_attachment_completeness(const struct gl_context *ctx, GLenum format,
          if (ctx->Extensions.ARB_depth_texture &&
              baseFormat == GL_DEPTH_STENCIL) {
             /* OK */
-         }
-         else {
+         } else if (ctx->Extensions.ARB_texture_stencil8 &&
+                    baseFormat == GL_STENCIL_INDEX) {
+            /* OK */
+         } else {
             /* no such thing as stencil-only textures */
             att_incomplete("illegal stencil texture");
             att->Complete = GL_FALSE;
@@ -978,7 +980,8 @@ _mesa_test_framebuffer_completeness(struct gl_context *ctx,
 
          if (!is_format_color_renderable(ctx, attFormat,
                                          texImg->InternalFormat) &&
-             !is_legal_depth_format(ctx, f)) {
+             !is_legal_depth_format(ctx, f) &&
+             f != GL_STENCIL_INDEX) {
             fb->_Status = GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
             fbo_incomplete(ctx, "texture attachment incomplete", -1);
             return;
diff --git a/src/mesa/main/texgetimage.c b/src/mesa/main/texgetimage.c
index 908bb9b1ce..92b4d6795c 100644
--- a/src/mesa/main/texgetimage.c
+++ b/src/mesa/main/texgetimage.c
@@ -175,6 +175,51 @@ get_tex_depth_stencil(struct gl_context *ctx, GLuint dimensions,
    }
 }
 
+/**
+ * glGetTexImage for stencil pixels.
+ */
+static void
+get_tex_stencil(struct gl_context *ctx, GLuint dimensions,
+                GLenum format, GLenum type, GLvoid *pixels,
+                struct gl_texture_image *texImage)
+{
+   const GLint width = texImage->Width;
+   const GLint height = texImage->Height;
+   const GLint depth = texImage->Depth;
+   GLint img, row;
+
+   assert(format == GL_STENCIL_INDEX);
+
+   for (img = 0; img < depth; img++) {
+      GLubyte *srcMap;
+      GLint rowstride;
+
+      /* map src texture buffer */
+      ctx->Driver.MapTextureImage(ctx, texImage, img,
+                                  0, 0, width, height, GL_MAP_READ_BIT,
+                                  &srcMap, &rowstride);
+
+      if (srcMap) {
+         for (row = 0; row < height; row++) {
+            const GLubyte *src = srcMap + row * rowstride;
+            void *dest = _mesa_image_address(dimensions, &ctx->Pack, pixels,
+                                             width, height, format, type,
+                                             img, row, 0);
+            _mesa_unpack_ubyte_stencil_row(texImage->TexFormat,
+                                           width,
+                                           (const GLuint *) src,
+                                           dest);
+         }
+
+         ctx->Driver.UnmapTextureImage(ctx, texImage, img);
+      }
+      else {
+         _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
+         break;
+      }
+   }
+}
+
 
 /**
  * glGetTexImage for YCbCr pixels.
@@ -684,6 +729,9 @@ _mesa_GetTexImage_sw(struct gl_context *ctx,
    else if (format == GL_DEPTH_STENCIL_EXT) {
       get_tex_depth_stencil(ctx, dimensions, format, type, pixels, texImage);
    }
+   else if (format == GL_STENCIL_INDEX) {
+      get_tex_stencil(ctx, dimensions, format, type, pixels, texImage);
+   }
    else if (format == GL_YCBCR_MESA) {
       get_tex_ycbcr(ctx, dimensions, format, type, pixels, texImage);
    }
@@ -879,7 +927,7 @@ getteximage_error_check(struct gl_context *ctx,
                   "glGetTex%sImage(format mismatch)", suffix);
       return GL_TRUE;
    }
-   else if (_mesa_is_enum_format_integer(format) !=
+   else if (!_mesa_is_stencil_format(format) && _mesa_is_enum_format_integer(format) !=
             _mesa_is_format_integer(texImage->TexFormat)) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glGetTex%sImage(format mismatch)", suffix);
diff --git a/src/mesa/main/teximage.c b/src/mesa/main/teximage.c
index 8d9d7cfc14..d07263c59b 100644
--- a/src/mesa/main/teximage.c
+++ b/src/mesa/main/teximage.c
@@ -1997,7 +1997,8 @@ _mesa_legal_texture_base_format_for_target(struct gl_context *ctx,
                                            const char *caller)
 {
    if (_mesa_base_tex_format(ctx, internalFormat) == GL_DEPTH_COMPONENT
-       || _mesa_base_tex_format(ctx, internalFormat) == GL_DEPTH_STENCIL) {
+       || _mesa_base_tex_format(ctx, internalFormat) == GL_DEPTH_STENCIL
+       || _mesa_base_tex_format(ctx, internalFormat) == GL_STENCIL_INDEX) {
       /* Section 3.8.3 (Texture Image Specification) of the OpenGL 3.3 Core
        * Profile spec says:
        *