/**************************************************************************
 * 
 * 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.
 * 
 **************************************************************************/


#include "draw/draw_pipe.h"
#include "util/u_math.h"
#include "util/u_memory.h"
#include "util/u_pack_color.h"

#include "i915_context.h"
#include "i915_reg.h"
#include "i915_state.h"
#include "i915_batch.h"


/**
 * Primitive emit to hardware.  No support for vertex buffers or any
 * nice fast paths.
 */
struct setup_stage {
   struct draw_stage stage; /**< This must be first (base class) */

   struct i915_context *i915;   
};


/**
 * Basically a cast wrapper.
 */
static INLINE struct setup_stage *setup_stage( struct draw_stage *stage )
{
   return (struct setup_stage *)stage;
}


/**
 * Extract the needed fields from vertex_header and emit i915 dwords.
 * Recall that the vertices are constructed by the 'draw' module and
 * have a couple of slots at the beginning (1-dword header, 4-dword
 * clip pos) that we ignore here.
 */
static INLINE void
emit_hw_vertex( struct i915_context *i915,
                const struct vertex_header *vertex)
{
   const struct vertex_info *vinfo = &i915->current.vertex_info;
   uint i;
   uint count = 0;  /* for debug/sanity */

   assert(!i915->dirty);

   for (i = 0; i < vinfo->num_attribs; i++) {
      const uint j = vinfo->attrib[i].src_index;
      const float *attrib = vertex->data[j];
      switch (vinfo->attrib[i].emit) {
      case EMIT_1F:
         OUT_BATCH( fui(attrib[0]) );
         count++;
         break;
      case EMIT_2F:
         OUT_BATCH( fui(attrib[0]) );
         OUT_BATCH( fui(attrib[1]) );
         count += 2;
         break;
      case EMIT_3F:
         OUT_BATCH( fui(attrib[0]) );
         OUT_BATCH( fui(attrib[1]) );
         OUT_BATCH( fui(attrib[2]) );
         count += 3;
         break;
      case EMIT_4F:
         OUT_BATCH( fui(attrib[0]) );
         OUT_BATCH( fui(attrib[1]) );
         OUT_BATCH( fui(attrib[2]) );
         OUT_BATCH( fui(attrib[3]) );
         count += 4;
         break;
      case EMIT_4UB:
         OUT_BATCH( pack_ub4(float_to_ubyte( attrib[0] ),
                             float_to_ubyte( attrib[1] ),
                             float_to_ubyte( attrib[2] ),
                             float_to_ubyte( attrib[3] )) );
         count += 1;
         break;
      case EMIT_4UB_BGRA:
         OUT_BATCH( pack_ub4(float_to_ubyte( attrib[2] ),
                             float_to_ubyte( attrib[1] ),
                             float_to_ubyte( attrib[0] ),
                             float_to_ubyte( attrib[3] )) );
         count += 1;
         break;
      default:
         assert(0);
      }
   }
   assert(count == vinfo->size);
}


static INLINE void 
emit_prim( struct draw_stage *stage, 
	   struct prim_header *prim,
	   unsigned hwprim,
	   unsigned nr )
{
   struct i915_context *i915 = setup_stage(stage)->i915;
   unsigned vertex_size;
   unsigned i;

   if (i915->dirty)
      i915_update_derived( i915 );

   if (i915->hardware_dirty)
      i915_emit_hardware_state( i915 );

   /* need to do this after validation! */
   vertex_size = i915->current.vertex_info.size * 4; /* in bytes */
   assert(vertex_size >= 12); /* never smaller than 12 bytes */

   if (!BEGIN_BATCH( 1 + nr * vertex_size / 4)) {
      FLUSH_BATCH(NULL);

      /* Make sure state is re-emitted after a flush: 
       */
      i915_emit_hardware_state( i915 );

      if (!BEGIN_BATCH( 1 + nr * vertex_size / 4)) {
	 assert(0);
	 return;
      }
   }

   /* Emit each triangle as a single primitive.  I told you this was
    * simple.
    */
   OUT_BATCH(_3DPRIMITIVE | 
	     hwprim |
	     ((4 + vertex_size * nr)/4 - 2));

   for (i = 0; i < nr; i++)
      emit_hw_vertex(i915, prim->v[i]);
}


static void 
setup_tri( struct draw_stage *stage, struct prim_header *prim )
{
   emit_prim( stage, prim, PRIM3D_TRILIST, 3 );
}


static void
setup_line(struct draw_stage *stage, struct prim_header *prim)
{
   emit_prim( stage, prim, PRIM3D_LINELIST, 2 );
}


static void
setup_point(struct draw_stage *stage, struct prim_header *prim)
{
   emit_prim( stage, prim, PRIM3D_POINTLIST, 1 );
}


static void setup_flush( struct draw_stage *stage, unsigned flags )
{
}

static void reset_stipple_counter( struct draw_stage *stage )
{
}

static void render_destroy( struct draw_stage *stage )
{
   FREE( stage );
}


/**
 * Create a new primitive setup/render stage.  This gets plugged into
 * the 'draw' module's pipeline.
 */
struct draw_stage *i915_draw_render_stage( struct i915_context *i915 )
{
   struct setup_stage *setup = CALLOC_STRUCT(setup_stage);

   setup->i915 = i915;
   setup->stage.draw = i915->draw;
   setup->stage.point = setup_point;
   setup->stage.line = setup_line;
   setup->stage.tri = setup_tri;
   setup->stage.flush = setup_flush;
   setup->stage.reset_stipple_counter = reset_stipple_counter;
   setup->stage.destroy = render_destroy;

   return &setup->stage;
}