mesa: Move _mesa_base_tex_format() from teximage to glformats files

This function will be needed as part of validating the combination of format,
type and internal format of texture pixel operations, which happens in
glformats files. Specifically, we want to be able to obtain the base format
of a resolved effective internal format, to compare it with the original
internal format passed.

Also, since this function deals solely with GL formats, it fits better in
glformats where the rest of similar format functionality rests.

The function is moved as-is, without any modification.

Cc: "11.0" <[email protected]>
Reviewed-by: Jason Ekstrand <[email protected]>
Tested-by: Mark Janes <[email protected]>

1 files changed, 505 insertions, 0 deletions

diff --git a/src/mesa/main/glformats.c b/src/mesa/main/glformats.c
index 6cfffdb4d51..515b06e14eb 100644
--- a/src/mesa/main/glformats.c
+++ b/src/mesa/main/glformats.c
@@ -2139,6 +2139,511 @@ _mesa_es_error_check_format_and_type(GLenum format, GLenum type,
    return type_valid ? GL_NO_ERROR : GL_INVALID_OPERATION;
 }
 
+/**
+ * Return the simple base format for a given internal texture format.
+ * For example, given GL_LUMINANCE12_ALPHA4, return GL_LUMINANCE_ALPHA.
+ *
+ * \param ctx GL context.
+ * \param internalFormat the internal texture format token or 1, 2, 3, or 4.
+ *
+ * \return the corresponding \u base internal format (GL_ALPHA, GL_LUMINANCE,
+ * GL_LUMANCE_ALPHA, GL_INTENSITY, GL_RGB, or GL_RGBA), or -1 if invalid enum.
+ *
+ * This is the format which is used during texture application (i.e. the
+ * texture format and env mode determine the arithmetic used.
+ */
+GLint
+_mesa_base_tex_format(const struct gl_context *ctx, GLint internalFormat)
+{
+   switch (internalFormat) {
+   case GL_ALPHA:
+   case GL_ALPHA4:
+   case GL_ALPHA8:
+   case GL_ALPHA12:
+   case GL_ALPHA16:
+      return (ctx->API != API_OPENGL_CORE) ? GL_ALPHA : -1;
+   case 1:
+   case GL_LUMINANCE:
+   case GL_LUMINANCE4:
+   case GL_LUMINANCE8:
+   case GL_LUMINANCE12:
+   case GL_LUMINANCE16:
+      return (ctx->API != API_OPENGL_CORE) ? GL_LUMINANCE : -1;
+   case 2:
+   case GL_LUMINANCE_ALPHA:
+   case GL_LUMINANCE4_ALPHA4:
+   case GL_LUMINANCE6_ALPHA2:
+   case GL_LUMINANCE8_ALPHA8:
+   case GL_LUMINANCE12_ALPHA4:
+   case GL_LUMINANCE12_ALPHA12:
+   case GL_LUMINANCE16_ALPHA16:
+      return (ctx->API != API_OPENGL_CORE) ? GL_LUMINANCE_ALPHA : -1;
+   case GL_INTENSITY:
+   case GL_INTENSITY4:
+   case GL_INTENSITY8:
+   case GL_INTENSITY12:
+   case GL_INTENSITY16:
+      return (ctx->API != API_OPENGL_CORE) ? GL_INTENSITY : -1;
+   case 3:
+      return (ctx->API != API_OPENGL_CORE) ? GL_RGB : -1;
+   case GL_RGB:
+   case GL_R3_G3_B2:
+   case GL_RGB4:
+   case GL_RGB5:
+   case GL_RGB8:
+   case GL_RGB10:
+   case GL_RGB12:
+   case GL_RGB16:
+      return GL_RGB;
+   case 4:
+      return (ctx->API != API_OPENGL_CORE) ? GL_RGBA : -1;
+   case GL_RGBA:
+   case GL_RGBA2:
+   case GL_RGBA4:
+   case GL_RGB5_A1:
+   case GL_RGBA8:
+   case GL_RGB10_A2:
+   case GL_RGBA12:
+   case GL_RGBA16:
+      return GL_RGBA;
+   default:
+      ; /* fallthrough */
+   }
+
+   /* GL_BGRA can be an internal format *only* in OpenGL ES (1.x or 2.0).
+    */
+   if (_mesa_is_gles(ctx)) {
+      switch (internalFormat) {
+      case GL_BGRA:
+         return GL_RGBA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ARB_ES2_compatibility) {
+      switch (internalFormat) {
+      case GL_RGB565:
+         return GL_RGB;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ARB_depth_texture) {
+      switch (internalFormat) {
+      case GL_DEPTH_COMPONENT:
+      case GL_DEPTH_COMPONENT16:
+      case GL_DEPTH_COMPONENT24:
+      case GL_DEPTH_COMPONENT32:
+         return GL_DEPTH_COMPONENT;
+      case GL_DEPTH_STENCIL:
+      case GL_DEPTH24_STENCIL8:
+         return GL_DEPTH_STENCIL;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ARB_texture_stencil8) {
+      switch (internalFormat) {
+      case GL_STENCIL_INDEX:
+      case GL_STENCIL_INDEX1:
+      case GL_STENCIL_INDEX4:
+      case GL_STENCIL_INDEX8:
+      case GL_STENCIL_INDEX16:
+         return GL_STENCIL_INDEX;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   switch (internalFormat) {
+   case GL_COMPRESSED_ALPHA:
+      return GL_ALPHA;
+   case GL_COMPRESSED_LUMINANCE:
+      return GL_LUMINANCE;
+   case GL_COMPRESSED_LUMINANCE_ALPHA:
+      return GL_LUMINANCE_ALPHA;
+   case GL_COMPRESSED_INTENSITY:
+      return GL_INTENSITY;
+   case GL_COMPRESSED_RGB:
+      return GL_RGB;
+   case GL_COMPRESSED_RGBA:
+      return GL_RGBA;
+   default:
+      ; /* fallthrough */
+   }
+
+   if (ctx->Extensions.TDFX_texture_compression_FXT1) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_RGB_FXT1_3DFX:
+         return GL_RGB;
+      case GL_COMPRESSED_RGBA_FXT1_3DFX:
+         return GL_RGBA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   /* Assume that the ANGLE flag will always be set if the EXT flag is set.
+    */
+   if (ctx->Extensions.ANGLE_texture_compression_dxt) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
+         return GL_RGB;
+      case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
+      case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
+      case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
+         return GL_RGBA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (_mesa_is_desktop_gl(ctx)
+       && ctx->Extensions.ANGLE_texture_compression_dxt) {
+      switch (internalFormat) {
+      case GL_RGB_S3TC:
+      case GL_RGB4_S3TC:
+         return GL_RGB;
+      case GL_RGBA_S3TC:
+      case GL_RGBA4_S3TC:
+         return GL_RGBA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.MESA_ycbcr_texture) {
+      if (internalFormat == GL_YCBCR_MESA)
+         return GL_YCBCR_MESA;
+   }
+
+   if (ctx->Extensions.ARB_texture_float) {
+      switch (internalFormat) {
+      case GL_ALPHA16F_ARB:
+      case GL_ALPHA32F_ARB:
+         return GL_ALPHA;
+      case GL_RGBA16F_ARB:
+      case GL_RGBA32F_ARB:
+         return GL_RGBA;
+      case GL_RGB16F_ARB:
+      case GL_RGB32F_ARB:
+         return GL_RGB;
+      case GL_INTENSITY16F_ARB:
+      case GL_INTENSITY32F_ARB:
+         return GL_INTENSITY;
+      case GL_LUMINANCE16F_ARB:
+      case GL_LUMINANCE32F_ARB:
+         return GL_LUMINANCE;
+      case GL_LUMINANCE_ALPHA16F_ARB:
+      case GL_LUMINANCE_ALPHA32F_ARB:
+         return GL_LUMINANCE_ALPHA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.EXT_texture_snorm) {
+      switch (internalFormat) {
+      case GL_RED_SNORM:
+      case GL_R8_SNORM:
+      case GL_R16_SNORM:
+         return GL_RED;
+      case GL_RG_SNORM:
+      case GL_RG8_SNORM:
+      case GL_RG16_SNORM:
+         return GL_RG;
+      case GL_RGB_SNORM:
+      case GL_RGB8_SNORM:
+      case GL_RGB16_SNORM:
+         return GL_RGB;
+      case GL_RGBA_SNORM:
+      case GL_RGBA8_SNORM:
+      case GL_RGBA16_SNORM:
+         return GL_RGBA;
+      case GL_ALPHA_SNORM:
+      case GL_ALPHA8_SNORM:
+      case GL_ALPHA16_SNORM:
+         return GL_ALPHA;
+      case GL_LUMINANCE_SNORM:
+      case GL_LUMINANCE8_SNORM:
+      case GL_LUMINANCE16_SNORM:
+         return GL_LUMINANCE;
+      case GL_LUMINANCE_ALPHA_SNORM:
+      case GL_LUMINANCE8_ALPHA8_SNORM:
+      case GL_LUMINANCE16_ALPHA16_SNORM:
+         return GL_LUMINANCE_ALPHA;
+      case GL_INTENSITY_SNORM:
+      case GL_INTENSITY8_SNORM:
+      case GL_INTENSITY16_SNORM:
+         return GL_INTENSITY;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.EXT_texture_sRGB) {
+      switch (internalFormat) {
+      case GL_SRGB_EXT:
+      case GL_SRGB8_EXT:
+      case GL_COMPRESSED_SRGB_EXT:
+         return GL_RGB;
+      case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
+         return ctx->Extensions.EXT_texture_compression_s3tc ? GL_RGB : -1;
+      case GL_SRGB_ALPHA_EXT:
+      case GL_SRGB8_ALPHA8_EXT:
+      case GL_COMPRESSED_SRGB_ALPHA_EXT:
+         return GL_RGBA;
+      case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
+      case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
+      case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
+         return ctx->Extensions.EXT_texture_compression_s3tc ? GL_RGBA : -1;
+      case GL_SLUMINANCE_ALPHA_EXT:
+      case GL_SLUMINANCE8_ALPHA8_EXT:
+      case GL_COMPRESSED_SLUMINANCE_ALPHA_EXT:
+         return GL_LUMINANCE_ALPHA;
+      case GL_SLUMINANCE_EXT:
+      case GL_SLUMINANCE8_EXT:
+      case GL_COMPRESSED_SLUMINANCE_EXT:
+         return GL_LUMINANCE;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Version >= 30 ||
+       ctx->Extensions.EXT_texture_integer) {
+      switch (internalFormat) {
+      case GL_RGBA8UI_EXT:
+      case GL_RGBA16UI_EXT:
+      case GL_RGBA32UI_EXT:
+      case GL_RGBA8I_EXT:
+      case GL_RGBA16I_EXT:
+      case GL_RGBA32I_EXT:
+      case GL_RGB10_A2UI:
+         return GL_RGBA;
+      case GL_RGB8UI_EXT:
+      case GL_RGB16UI_EXT:
+      case GL_RGB32UI_EXT:
+      case GL_RGB8I_EXT:
+      case GL_RGB16I_EXT:
+      case GL_RGB32I_EXT:
+         return GL_RGB;
+      }
+   }
+
+   if (ctx->Extensions.EXT_texture_integer) {
+      switch (internalFormat) {
+      case GL_ALPHA8UI_EXT:
+      case GL_ALPHA16UI_EXT:
+      case GL_ALPHA32UI_EXT:
+      case GL_ALPHA8I_EXT:
+      case GL_ALPHA16I_EXT:
+      case GL_ALPHA32I_EXT:
+         return GL_ALPHA;
+      case GL_INTENSITY8UI_EXT:
+      case GL_INTENSITY16UI_EXT:
+      case GL_INTENSITY32UI_EXT:
+      case GL_INTENSITY8I_EXT:
+      case GL_INTENSITY16I_EXT:
+      case GL_INTENSITY32I_EXT:
+         return GL_INTENSITY;
+      case GL_LUMINANCE8UI_EXT:
+      case GL_LUMINANCE16UI_EXT:
+      case GL_LUMINANCE32UI_EXT:
+      case GL_LUMINANCE8I_EXT:
+      case GL_LUMINANCE16I_EXT:
+      case GL_LUMINANCE32I_EXT:
+         return GL_LUMINANCE;
+      case GL_LUMINANCE_ALPHA8UI_EXT:
+      case GL_LUMINANCE_ALPHA16UI_EXT:
+      case GL_LUMINANCE_ALPHA32UI_EXT:
+      case GL_LUMINANCE_ALPHA8I_EXT:
+      case GL_LUMINANCE_ALPHA16I_EXT:
+      case GL_LUMINANCE_ALPHA32I_EXT:
+         return GL_LUMINANCE_ALPHA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ARB_texture_rg) {
+      switch (internalFormat) {
+      case GL_R16F:
+      case GL_R32F:
+	 if (!ctx->Extensions.ARB_texture_float)
+	    break;
+         return GL_RED;
+      case GL_R8I:
+      case GL_R8UI:
+      case GL_R16I:
+      case GL_R16UI:
+      case GL_R32I:
+      case GL_R32UI:
+	 if (ctx->Version < 30 && !ctx->Extensions.EXT_texture_integer)
+	    break;
+	 /* FALLTHROUGH */
+      case GL_R8:
+      case GL_R16:
+      case GL_RED:
+      case GL_COMPRESSED_RED:
+         return GL_RED;
+
+      case GL_RG16F:
+      case GL_RG32F:
+	 if (!ctx->Extensions.ARB_texture_float)
+	    break;
+         return GL_RG;
+      case GL_RG8I:
+      case GL_RG8UI:
+      case GL_RG16I:
+      case GL_RG16UI:
+      case GL_RG32I:
+      case GL_RG32UI:
+	 if (ctx->Version < 30 && !ctx->Extensions.EXT_texture_integer)
+	    break;
+	 /* FALLTHROUGH */
+      case GL_RG:
+      case GL_RG8:
+      case GL_RG16:
+      case GL_COMPRESSED_RG:
+         return GL_RG;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.EXT_texture_shared_exponent) {
+      switch (internalFormat) {
+      case GL_RGB9_E5_EXT:
+         return GL_RGB;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.EXT_packed_float) {
+      switch (internalFormat) {
+      case GL_R11F_G11F_B10F_EXT:
+         return GL_RGB;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ARB_depth_buffer_float) {
+      switch (internalFormat) {
+      case GL_DEPTH_COMPONENT32F:
+         return GL_DEPTH_COMPONENT;
+      case GL_DEPTH32F_STENCIL8:
+         return GL_DEPTH_STENCIL;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ARB_texture_compression_rgtc) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_RED_RGTC1:
+      case GL_COMPRESSED_SIGNED_RED_RGTC1:
+         return GL_RED;
+      case GL_COMPRESSED_RG_RGTC2:
+      case GL_COMPRESSED_SIGNED_RG_RGTC2:
+         return GL_RG;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.EXT_texture_compression_latc) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
+      case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
+         return GL_LUMINANCE;
+      case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
+      case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
+         return GL_LUMINANCE_ALPHA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.ATI_texture_compression_3dc) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
+         return GL_LUMINANCE_ALPHA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->Extensions.OES_compressed_ETC1_RGB8_texture) {
+      switch (internalFormat) {
+      case GL_ETC1_RGB8_OES:
+         return GL_RGB;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (_mesa_is_gles3(ctx) || ctx->Extensions.ARB_ES3_compatibility) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_RGB8_ETC2:
+      case GL_COMPRESSED_SRGB8_ETC2:
+         return GL_RGB;
+      case GL_COMPRESSED_RGBA8_ETC2_EAC:
+      case GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC:
+      case GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2:
+      case GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2:
+         return GL_RGBA;
+      case GL_COMPRESSED_R11_EAC:
+      case GL_COMPRESSED_SIGNED_R11_EAC:
+         return GL_RED;
+      case GL_COMPRESSED_RG11_EAC:
+      case GL_COMPRESSED_SIGNED_RG11_EAC:
+         return GL_RG;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (_mesa_is_desktop_gl(ctx) &&
+       ctx->Extensions.ARB_texture_compression_bptc) {
+      switch (internalFormat) {
+      case GL_COMPRESSED_RGBA_BPTC_UNORM:
+      case GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM:
+         return GL_RGBA;
+      case GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT:
+      case GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT:
+         return GL_RGB;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   if (ctx->API == API_OPENGLES) {
+      switch (internalFormat) {
+      case GL_PALETTE4_RGB8_OES:
+      case GL_PALETTE4_R5_G6_B5_OES:
+      case GL_PALETTE8_RGB8_OES:
+      case GL_PALETTE8_R5_G6_B5_OES:
+	 return GL_RGB;
+      case GL_PALETTE4_RGBA8_OES:
+      case GL_PALETTE8_RGB5_A1_OES:
+      case GL_PALETTE4_RGBA4_OES:
+      case GL_PALETTE4_RGB5_A1_OES:
+      case GL_PALETTE8_RGBA8_OES:
+      case GL_PALETTE8_RGBA4_OES:
+	 return GL_RGBA;
+      default:
+         ; /* fallthrough */
+      }
+   }
+
+   return -1; /* error */
+}
 
 /**
  * Do error checking of format/type combinations for OpenGL ES 3