From: Ian Romanick Date: Thu, 29 Apr 2010 01:42:36 +0000 (-0700) Subject: Define IR instruction for texture look-ups X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=81377c012cf5db3efe2e39885846c60b6e5c6eb8;p=mesa.git Define IR instruction for texture look-ups --- diff --git a/ir.h b/ir.h index bf3400aa921..fcb23ea0fab 100644 --- a/ir.h +++ b/ir.h @@ -737,6 +737,83 @@ private: /*@}*/ +/** + * Texture sampling opcodes used in ir_texture + */ +enum ir_texture_opcode { + ir_tex, /* Regular texture look-up */ + ir_txb, /* Texture look-up with LOD bias */ + ir_txl, /* Texture look-up with explicit LOD */ + ir_txd, /* Texture look-up with partial derivatvies */ + ir_txf /* Texel fetch with explicit LOD */ +}; + + +/** + * IR instruction to sample a texture + * + * The specific form of the IR instruction depends on the \c mode value + * selected from \c ir_texture_opcodes. In the printed IR, these will + * appear as: + * + * Texel offset + * | Projection divisor + * | | Shadow comparitor + * | | | + * v v v + * (tex (sampler) (coordinate) (0 0 0) (1) ( )) + * (txb (sampler) (coordinate) (0 0 0) (1) ( ) (bias)) + * (txl (sampler) (coordinate) (0 0 0) (1) ( ) (lod)) + * (txd (sampler) (coordinate) (0 0 0) (1) ( ) (dPdx dPdy)) + * (txf (sampler) (coordinate) (0 0 0) (lod)) + */ +class ir_texture : public ir_rvalue { +public: + ir_texture(enum ir_texture_opcode op) + : op(op) + { + /* empty */ + } + + enum ir_texture_opcode op; + + /** Sampler to use for the texture access. */ + ir_dereference *sampler; + + /** Texture coordinate to sample */ + ir_rvalue *coordinate; + + /** + * Value used for projective divide. + * + * If there is no projective divide (the common case), this will be + * \c NULL. Optimization passes should check for this to point to a constant + * of 1.0 and replace that with \c NULL. + */ + ir_rvalue *projector; + + /** + * Coordinate used for comparison on shadow look-ups. + * + * If there is no shadow comparison, this will be \c NULL. For the + * \c ir_txf opcode, this *must* be \c NULL. + */ + ir_rvalue *shadow_comparitor; + + /** Explicit texel offsets. */ + signed char offsets[3]; + + union { + ir_rvalue *lod; /**< Floating point LOD */ + ir_rvalue *bias; /**< Floating point LOD bias */ + struct { + ir_rvalue *dPdx; /**< Partial derivative of coordinate wrt X */ + ir_rvalue *dPdy; /**< Partial derivative of coordinate wrt Y */ + } grad; + } lod_info; +}; + + struct ir_swizzle_mask { unsigned x:2; unsigned y:2;