[Mesa-dev] [PATCH v5 3/3] mesa: Use the effective internal format instead for validation

Eduardo Lima Mitev elima at igalia.com
Thu Sep 24 01:57:43 PDT 2015


When validating format+type+internalFormat for texture pixel operations
on GLES3, the effective internal format should be used if the one
specified is an unsized internal format. Page 127, section "3.8 Texturing"
of the GLES 3.0.4 spec says:

    "if internalformat is a base internal format, the effective internal
     format is a sized internal format that is derived from the format and
     type for internal use by the GL. Table 3.12 specifies the mapping of
     format and type to effective internal formats. The effective internal
     format is used by the GL for purposes such as texture completeness or
     type checks for CopyTex* commands. In these cases, the GL is required
     to operate as if the effective internal format was used as the
     internalformat when specifying the texture data."

v2: Per the spec, Luminance8Alpha8, Luminance8 and Alpha8 should not be
considered sized internal formats. Return the corresponding unsize format
instead.

v4: * Improved comments in
      _mesa_es3_effective_internal_format_for_format_and_type().
    * Splitted patch to separate chunk about reordering of
      error_check_subtexture_dimensions() error check, which is not directly
      related with this patch.
v5: Dropped the splitted patch because it was actually a work around 3
    dEQP tests that are buggy:

    dEQP-GLES2.functional.negative_api.texture.texsubimage2d_neg_offset
    dEQP-GLES2.functional.negative_api.texture.texsubimage2d_offset_allowed
    dEQP-GLES2.functional.negative_api.texture.texsubimage2d_neg_wdt_hgt

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91582
---
 src/mesa/main/glformats.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 151 insertions(+)

diff --git a/src/mesa/main/glformats.c b/src/mesa/main/glformats.c
index 515b06e..7dab33c 100644
--- a/src/mesa/main/glformats.c
+++ b/src/mesa/main/glformats.c
@@ -2646,6 +2646,127 @@ _mesa_base_tex_format(const struct gl_context *ctx, GLint internalFormat)
 }
 
 /**
+ * Returns the effective internal format from a texture format and type.
+ * This is used by texture image operations internally for validation, when
+ * the specified internal format is a base (unsized) format.
+ *
+ * This method will only return a valid effective internal format if the
+ * combination of format, type and internal format in base form, is acceptable.
+ *
+ * If a single sized internal format is defined in the spec (OpenGL-ES 3.0.4) or
+ * in extensions, to unambiguously correspond to the given base format, then
+ * that internal format is returned as the effective. Otherwise, if the
+ * combination is accepted but a single effective format is not defined, the
+ * passed base format will be returned instead.
+ *
+ * \param format the texture format
+ * \param type the texture type
+ */
+static GLenum
+_mesa_es3_effective_internal_format_for_format_and_type(GLenum format,
+                                                        GLenum type)
+{
+   switch (type) {
+   case GL_UNSIGNED_BYTE:
+      switch (format) {
+      case GL_RGBA:
+         return GL_RGBA8;
+      case GL_RGB:
+         return GL_RGB8;
+      /* Although LUMINANCE_ALPHA, LUMINANCE and ALPHA appear in table 3.12,
+       * (section 3.8 Texturing, page 128 of the OpenGL-ES 3.0.4) as effective
+       * internal formats, they do not correspond to GL constants, so the base
+       * format is returned instead.
+       */
+      case GL_LUMINANCE_ALPHA:
+      case GL_LUMINANCE:
+      case GL_ALPHA:
+         return format;
+      }
+      break;
+
+   case GL_UNSIGNED_SHORT_4_4_4_4:
+      if (format == GL_RGBA)
+         return GL_RGBA4;
+      break;
+
+   case GL_UNSIGNED_SHORT_5_5_5_1:
+      if (format == GL_RGBA)
+         return GL_RGB5_A1;
+      break;
+
+   case GL_UNSIGNED_SHORT_5_6_5:
+      if (format == GL_RGB)
+         return GL_RGB565;
+      break;
+
+   /* OES_packed_depth_stencil */
+   case GL_UNSIGNED_INT_24_8:
+      if (format == GL_DEPTH_STENCIL)
+         return GL_DEPTH24_STENCIL8;
+      break;
+
+   case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
+      if (format == GL_DEPTH_STENCIL)
+         return GL_DEPTH32F_STENCIL8;
+      break;
+
+   case GL_UNSIGNED_SHORT:
+      if (format == GL_DEPTH_COMPONENT)
+         return GL_DEPTH_COMPONENT16;
+      break;
+
+   case GL_UNSIGNED_INT:
+      /* It can be DEPTH_COMPONENT16 or DEPTH_COMPONENT24, so just return
+       * the format.
+       */
+      if (format == GL_DEPTH_COMPONENT)
+         return format;
+      break;
+
+   /* OES_texture_float and OES_texture_half_float */
+   case GL_FLOAT:
+      if (format == GL_DEPTH_COMPONENT)
+         return GL_DEPTH_COMPONENT32F;
+      /* fall through */
+   case GL_HALF_FLOAT_OES:
+      switch (format) {
+      case GL_RGBA:
+      case GL_RGB:
+      case GL_LUMINANCE_ALPHA:
+      case GL_LUMINANCE:
+      case GL_ALPHA:
+      case GL_RED:
+      case GL_RG:
+         return format;
+      }
+      break;
+   case GL_HALF_FLOAT:
+      switch (format) {
+      case GL_RG:
+      case GL_RED:
+         return format;
+      }
+      break;
+
+   /* GL_EXT_texture_type_2_10_10_10_REV */
+   case GL_UNSIGNED_INT_2_10_10_10_REV:
+      switch (format) {
+      case GL_RGBA:
+      case GL_RGB:
+         return format;
+      }
+      break;
+
+   default:
+      /* fall through and return NONE */
+      break;
+   }
+
+   return GL_NONE;
+}
+
+/**
  * Do error checking of format/type combinations for OpenGL ES 3
  * glTex[Sub]Image.
  * \return error code, or GL_NO_ERROR.
@@ -2655,6 +2776,36 @@ _mesa_es3_error_check_format_and_type(const struct gl_context *ctx,
                                       GLenum format, GLenum type,
                                       GLenum internalFormat)
 {
+   /* If internalFormat is an unsized format, then the effective internal
+    * format derived from format and type should be used instead. Page 127,
+    * section "3.8 Texturing" of the GLES 3.0.4 spec states:
+    *
+    *    "if internalformat is a base internal format, the effective
+    *     internal format is a sized internal format that is derived
+    *     from the format and type for internal use by the GL.
+    *     Table 3.12 specifies the mapping of format and type to effective
+    *     internal formats. The effective internal format is used by the GL
+    *     for purposes such as texture completeness or type checks for
+    *     CopyTex* commands. In these cases, the GL is required to operate
+    *     as if the effective internal format was used as the internalformat
+    *     when specifying the texture data."
+    */
+   if (_mesa_is_enum_format_unsized(internalFormat)) {
+      GLenum effectiveInternalFormat =
+         _mesa_es3_effective_internal_format_for_format_and_type(format, type);
+
+      if (effectiveInternalFormat == GL_NONE)
+         return GL_INVALID_OPERATION;
+
+      GLenum baseInternalFormat =
+         _mesa_base_tex_format(ctx, effectiveInternalFormat);
+
+      if (internalFormat != baseInternalFormat)
+         return GL_INVALID_OPERATION;
+
+      internalFormat = effectiveInternalFormat;
+   }
+
    switch (format) {
    case GL_RGBA:
       switch (type) {
-- 
2.4.6



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