teximage: Add utility func for format/internalFormat compatibility check

In texture_error_check() there was a snippet of code to check whether the
given format and internal format are basically compatible. This has been split
out into its own static helper function so that it can be used by an
implementation of glClearTexImage too.

diff --git a/src/mesa/main/teximage.c b/src/mesa/main/teximage.c
index 3fba6f1b2d5f5438dd4363dad3b8ac7cac64a49d..b972cc187ad76437db1728021619e3f404273174 100644 (file)
--- a/src/mesa/main/teximage.c
+++ b/src/mesa/main/teximage.c
@@ -2010,6 +2010,43 @@ _mesa_legal_texture_base_format_for_target(struct gl_context *ctx,
    return true;
 }
 
+static bool
+texture_formats_agree(GLenum internalFormat,
+                      GLenum format)
+{
+   GLboolean colorFormat;
+   GLboolean is_format_depth_or_depthstencil;
+   GLboolean is_internalFormat_depth_or_depthstencil;
+
+   /* Even though there are no color-index textures, we still have to support
+    * uploading color-index data and remapping it to RGB via the
+    * GL_PIXEL_MAP_I_TO_[RGBA] tables.
+    */
+   const GLboolean indexFormat = (format == GL_COLOR_INDEX);
+
+   is_internalFormat_depth_or_depthstencil =
+      _mesa_is_depth_format(internalFormat) ||
+      _mesa_is_depthstencil_format(internalFormat);
+
+   is_format_depth_or_depthstencil =
+      _mesa_is_depth_format(format) ||
+      _mesa_is_depthstencil_format(format);
+
+   colorFormat = _mesa_is_color_format(format);
+
+   if (_mesa_is_color_format(internalFormat) && !colorFormat && !indexFormat)
+      return false;
+
+   if (is_internalFormat_depth_or_depthstencil !=
+       is_format_depth_or_depthstencil)
+      return false;
+
+   if (_mesa_is_ycbcr_format(internalFormat) != _mesa_is_ycbcr_format(format))
+      return false;
+
+   return true;
+}
+
 /**
  * Test the glTexImage[123]D() parameters for errors.
  *
@@ -2043,17 +2080,8 @@ texture_error_check( struct gl_context *ctx,
                      GLint width, GLint height,
                      GLint depth, GLint border )
 {
-   GLboolean colorFormat;
-   GLboolean is_format_depth_or_depthstencil;
-   GLboolean is_internalFormat_depth_or_depthstencil;
    GLenum err;
 
-   /* Even though there are no color-index textures, we still have to support
-    * uploading color-index data and remapping it to RGB via the
-    * GL_PIXEL_MAP_I_TO_[RGBA] tables.
-    */
-   const GLboolean indexFormat = (format == GL_COLOR_INDEX);
-
    /* Note: for proxy textures, some error conditions immediately generate
     * a GL error in the usual way.  But others do not generate a GL error.
     * Instead, they cause the width, height, depth, format fields of the
@@ -2136,18 +2164,7 @@ texture_error_check( struct gl_context *ctx,
    }
 
    /* make sure internal format and format basically agree */
-   is_internalFormat_depth_or_depthstencil =
-      _mesa_is_depth_format(internalFormat) ||
-      _mesa_is_depthstencil_format(internalFormat);
-
-   is_format_depth_or_depthstencil =
-      _mesa_is_depth_format(format) ||
-      _mesa_is_depthstencil_format(format);
-
-   colorFormat = _mesa_is_color_format(format);
-   if ((_mesa_is_color_format(internalFormat) && !colorFormat && !indexFormat) ||
-       (is_internalFormat_depth_or_depthstencil != is_format_depth_or_depthstencil) ||
-       (_mesa_is_ycbcr_format(internalFormat) != _mesa_is_ycbcr_format(format))) {
+   if (!texture_formats_agree(internalFormat, format)) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glTexImage%dD(incompatible internalFormat = %s, format = %s)",
                   dimensions, _mesa_lookup_enum_by_nr(internalFormat),