src/gallium/auxiliary/draw/draw_pt.h

/**************************************************************************
 * 
 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
 * All Rights Reserved.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 **************************************************************************/

 /*
  * Authors:
  *   Keith Whitwell <keith@tungstengraphics.com>
  */

#ifndef DRAW_PT_H
#define DRAW_PT_H

#include "pipe/p_compiler.h"

typedef unsigned (*pt_elt_func)( const void *elts, unsigned idx );

struct draw_pt_middle_end;
struct draw_context;


#define PT_SHADE      0x1
#define PT_CLIPTEST   0x2
#define PT_PIPELINE   0x4
#define PT_MAX_MIDDLE 0x8


/* The "front end" - prepare sets of fetch, draw elements for the
 * middle end.
 *
 * Currenly one version of this:
 *    - vcache - catchall implementation, decomposes to TRI/LINE/POINT prims
 * Later:
 *    - varray, varray_split
 *    - velement, velement_split
 *
 * Currenly only using the vcache version.
 */
struct draw_pt_front_end {
   void (*prepare)( struct draw_pt_front_end *,
                    unsigned prim,
                    struct draw_pt_middle_end *,
		    unsigned opt );

   void (*run)( struct draw_pt_front_end *,
                pt_elt_func elt_func,
                const void *elt_ptr,
                unsigned count );

   void (*finish)( struct draw_pt_front_end * );
   void (*destroy)( struct draw_pt_front_end * );
};


/* The "middle end" - prepares actual hardware vertices for the
 * hardware backend.
 *
 * Currently two versions of this:
 *     - fetch, vertex shade, cliptest, prim-pipeline
 *     - fetch, emit (ie passthrough)
 */
struct draw_pt_middle_end {
   void (*prepare)( struct draw_pt_middle_end *,
                    unsigned prim,
		    unsigned opt,
                    unsigned *max_vertices );

   void (*run)( struct draw_pt_middle_end *,
                const unsigned *fetch_elts,
                unsigned fetch_count,
                const ushort *draw_elts,
                unsigned draw_count );

   void (*run_linear)(struct draw_pt_middle_end *,
                      unsigned start,
                      unsigned count);

   /* Transform all vertices in a linear range and then draw them with
    * the supplied element list.  May fail and return FALSE.
    */
   boolean (*run_linear_elts)( struct draw_pt_middle_end *,
                            unsigned fetch_start,
                            unsigned fetch_count,
                            const ushort *draw_elts,
                            unsigned draw_count );

   int (*get_max_vertex_count)( struct draw_pt_middle_end * );

   void (*finish)( struct draw_pt_middle_end * );
   void (*destroy)( struct draw_pt_middle_end * );
};


/* The "back end" - supplied by the driver, defined in draw_vbuf.h.
 */
struct vbuf_render;
struct vertex_header;


/* Helper functions.
 */
pt_elt_func draw_pt_elt_func( struct draw_context *draw );
const void *draw_pt_elt_ptr( struct draw_context *draw,
                             unsigned start );

/* Frontends: 
 *
 * Currently only the general-purpose vcache implementation, could add
 * a special case for tiny vertex buffers.
 */
struct draw_pt_front_end *draw_pt_vcache( struct draw_context *draw );
struct draw_pt_front_end *draw_pt_varray(struct draw_context *draw);


/* Middle-ends:
 *
 * Currently one general-purpose case which can do all possibilities,
 * at the slight expense of creating a vertex_header in some cases
 * unecessarily.
 *
 * The special case fetch_emit code avoids pipeline vertices
 * altogether and builds hardware vertices directly from API
 * vertex_elements.
 */
struct draw_pt_middle_end *draw_pt_fetch_emit( struct draw_context *draw );
struct draw_pt_middle_end *draw_pt_middle_fse( struct draw_context *draw );
struct draw_pt_middle_end *draw_pt_fetch_pipeline_or_emit(struct draw_context *draw);


/* More helpers:
 */
boolean draw_pt_get_edgeflag( struct draw_context *draw,
                              unsigned idx );


/*******************************************************************************
 * HW vertex emit:
 */
struct pt_emit;

void draw_pt_emit_prepare( struct pt_emit *emit,
			   unsigned prim,
                           unsigned *max_vertices );

void draw_pt_emit( struct pt_emit *emit,
		   const float (*vertex_data)[4],
		   unsigned vertex_count,
		   unsigned stride,
		   const ushort *elts,
		   unsigned count );

void draw_pt_emit_linear( struct pt_emit *emit,
                          const float (*vertex_data)[4],
                          unsigned stride,
                          unsigned count );

void draw_pt_emit_destroy( struct pt_emit *emit );

struct pt_emit *draw_pt_emit_create( struct draw_context *draw );


/*******************************************************************************
 * API vertex fetch:
 */

struct pt_fetch;
void draw_pt_fetch_prepare( struct pt_fetch *fetch,
                            unsigned vertex_input_count,
			    unsigned vertex_size );

void draw_pt_fetch_run( struct pt_fetch *fetch,
			const unsigned *elts,
			unsigned count,
			char *verts );

void draw_pt_fetch_run_linear( struct pt_fetch *fetch,
                               unsigned start,
                               unsigned count,
                               char *verts );

void draw_pt_fetch_destroy( struct pt_fetch *fetch );

struct pt_fetch *draw_pt_fetch_create( struct draw_context *draw );

/*******************************************************************************
 * Post-VS: cliptest, rhw, viewport
 */
struct pt_post_vs;

boolean draw_pt_post_vs_run( struct pt_post_vs *pvs,
			     struct vertex_header *pipeline_verts,
			     unsigned stride,
			     unsigned count );

void draw_pt_post_vs_prepare( struct pt_post_vs *pvs,
			      boolean bypass_clipping,
			      boolean bypass_viewport,
			      boolean opengl );

struct pt_post_vs *draw_pt_post_vs_create( struct draw_context *draw );

void draw_pt_post_vs_destroy( struct pt_post_vs *pvs );


/*******************************************************************************
 * Utils: 
 */
void draw_pt_split_prim(unsigned prim, unsigned *first, unsigned *incr);


#endif