Subversion Repositories Kolibri OS

/*

 * Mesa 3-D graphics library

 * Version:  7.0.3

 *

 * Copyright (C) 1999-2007  Brian Paul   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, sublicense,

 * 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 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 NONINFRINGEMENT.  IN NO EVENT SHALL

 * BRIAN PAUL 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 "main/glheader.h"

#include "main/colormac.h"

#include "program/prog_instruction.h"

#include "s_context.h"

#include "s_fragprog.h"

#include "s_span.h"

/**

 * Apply texture object's swizzle (X/Y/Z/W/0/1) to incoming 'texel'

 * and return results in 'colorOut'.

 */

static INLINE void

swizzle_texel(const GLfloat texel[4], GLfloat colorOut[4], GLuint swizzle)

{

   if (swizzle == SWIZZLE_NOOP) {

      COPY_4V(colorOut, texel);

   }

   else {

      GLfloat vector[6];

      vector[SWIZZLE_X] = texel[0];

      vector[SWIZZLE_Y] = texel[1];

      vector[SWIZZLE_Z] = texel[2];

      vector[SWIZZLE_W] = texel[3];

      vector[SWIZZLE_ZERO] = 0.0F;

      vector[SWIZZLE_ONE] = 1.0F;

      colorOut[0] = vector[GET_SWZ(swizzle, 0)];

      colorOut[1] = vector[GET_SWZ(swizzle, 1)];

      colorOut[2] = vector[GET_SWZ(swizzle, 2)];

      colorOut[3] = vector[GET_SWZ(swizzle, 3)];

   }

}

/**

 * Fetch a texel with given lod.

 * Called via machine->FetchTexelLod()

 */

static void

fetch_texel_lod( struct gl_context *ctx, const GLfloat texcoord[4], GLfloat lambda,

                 GLuint unit, GLfloat color[4] )

{

   const struct gl_texture_object *texObj = ctx->Texture.Unit[unit]._Current;

   if (texObj) {

      SWcontext *swrast = SWRAST_CONTEXT(ctx);

      GLfloat rgba[4];

      lambda = CLAMP(lambda, texObj->MinLod, texObj->MaxLod);

      swrast->TextureSample[unit](ctx, texObj, 1,

                                  (const GLfloat (*)[4]) texcoord,

                                  &lambda, &rgba);

      swizzle_texel(rgba, color, texObj->_Swizzle);

   }

   else {

      ASSIGN_4V(color, 0.0F, 0.0F, 0.0F, 1.0F);

   }

}

/**

 * Fetch a texel with the given partial derivatives to compute a level

 * of detail in the mipmap.

 * Called via machine->FetchTexelDeriv()

 * \param lodBias  the lod bias which may be specified by a TXB instruction,

 *                 otherwise zero.

 */

static void

fetch_texel_deriv( struct gl_context *ctx, const GLfloat texcoord[4],

                   const GLfloat texdx[4], const GLfloat texdy[4],

                   GLfloat lodBias, GLuint unit, GLfloat color[4] )

{

   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];

   const struct gl_texture_object *texObj = texUnit->_Current;

   if (texObj) {

      const struct gl_texture_image *texImg =

         texObj->Image[0][texObj->BaseLevel];

      const GLfloat texW = (GLfloat) texImg->WidthScale;

      const GLfloat texH = (GLfloat) texImg->HeightScale;

      GLfloat lambda;

      GLfloat rgba[4];

      lambda = _swrast_compute_lambda(texdx[0], texdy[0], /* ds/dx, ds/dy */

                                      texdx[1], texdy[1], /* dt/dx, dt/dy */

                                      texdx[3], texdy[3], /* dq/dx, dq/dy */

                                      texW, texH,

                                      texcoord[0], texcoord[1], texcoord[3],

                                      1.0F / texcoord[3]);

      lambda += lodBias + texUnit->LodBias + texObj->LodBias;

      lambda = CLAMP(lambda, texObj->MinLod, texObj->MaxLod);

      swrast->TextureSample[unit](ctx, texObj, 1,

                                  (const GLfloat (*)[4]) texcoord,

                                  &lambda, &rgba);

      swizzle_texel(rgba, color, texObj->_Swizzle);

   }

   else {

      ASSIGN_4V(color, 0.0F, 0.0F, 0.0F, 1.0F);

   }

}

/**

 * Initialize the virtual fragment program machine state prior to running

 * fragment program on a fragment.  This involves initializing the input

 * registers, condition codes, etc.

 * \param machine  the virtual machine state to init

 * \param program  the fragment program we're about to run

 * \param span  the span of pixels we'll operate on

 * \param col  which element (column) of the span we'll operate on

 */

static void

init_machine(struct gl_context *ctx, struct gl_program_machine *machine,

             const struct gl_fragment_program *program,

             const SWspan *span, GLuint col)

{

   GLfloat *wpos = span->array->attribs[FRAG_ATTRIB_WPOS][col];

   if (program->Base.Target == GL_FRAGMENT_PROGRAM_NV) {

      /* Clear temporary registers (undefined for ARB_f_p) */

      memset(machine->Temporaries, 0, MAX_PROGRAM_TEMPS * 4 * sizeof(GLfloat));

   }

   /* ARB_fragment_coord_conventions */

   if (program->OriginUpperLeft)

      wpos[1] = ctx->DrawBuffer->Height - 1 - wpos[1];

   if (!program->PixelCenterInteger) {

      wpos[0] += 0.5F;

      wpos[1] += 0.5F;

   }

   /* Setup pointer to input attributes */

   machine->Attribs = span->array->attribs;

   machine->DerivX = (GLfloat (*)[4]) span->attrStepX;

   machine->DerivY = (GLfloat (*)[4]) span->attrStepY;

   machine->NumDeriv = FRAG_ATTRIB_MAX;

   machine->Samplers = program->Base.SamplerUnits;

   /* if running a GLSL program (not ARB_fragment_program) */

   if (ctx->Shader.CurrentFragmentProgram) {

      /* Store front/back facing value */

      machine->Attribs[FRAG_ATTRIB_FACE][col][0] = 1.0F - span->facing;

   }

   machine->CurElement = col;

   /* init condition codes */

   machine->CondCodes[0] = COND_EQ;

   machine->CondCodes[1] = COND_EQ;

   machine->CondCodes[2] = COND_EQ;

   machine->CondCodes[3] = COND_EQ;

   /* init call stack */

   machine->StackDepth = 0;

   machine->FetchTexelLod = fetch_texel_lod;

   machine->FetchTexelDeriv = fetch_texel_deriv;

}

/**

 * Run fragment program on the pixels in span from 'start' to 'end' - 1.

 */

static void

run_program(struct gl_context *ctx, SWspan *span, GLuint start, GLuint end)

{

   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   const struct gl_fragment_program *program = ctx->FragmentProgram._Current;

   const GLbitfield64 outputsWritten = program->Base.OutputsWritten;

   struct gl_program_machine *machine = &swrast->FragProgMachine;

   GLuint i;

   for (i = start; i < end; i++) {

      if (span->array->mask[i]) {

         init_machine(ctx, machine, program, span, i);

         if (_mesa_execute_program(ctx, &program->Base, machine)) {

            /* Store result color */

	    if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_COLOR)) {

               COPY_4V(span->array->attribs[FRAG_ATTRIB_COL0][i],

                       machine->Outputs[FRAG_RESULT_COLOR]);

            }

            else {

               /* Multiple drawbuffers / render targets

                * Note that colors beyond 0 and 1 will overwrite other

                * attributes, such as FOGC, TEX0, TEX1, etc.  That's OK.

                */

               GLuint buf;

               for (buf = 0; buf < ctx->DrawBuffer->_NumColorDrawBuffers; buf++) {

                  if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DATA0 + buf)) {

                     COPY_4V(span->array->attribs[FRAG_ATTRIB_COL0 + buf][i],

                             machine->Outputs[FRAG_RESULT_DATA0 + buf]);

                  }

               }

            }

            /* Store result depth/z */

            if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {

               const GLfloat depth = machine->Outputs[FRAG_RESULT_DEPTH][2];

               if (depth <= 0.0)

                  span->array->z[i] = 0;

               else if (depth >= 1.0)

                  span->array->z[i] = ctx->DrawBuffer->_DepthMax;

               else

                  span->array->z[i] = IROUND(depth * ctx->DrawBuffer->_DepthMaxF);

            }

         }

         else {

            /* killed fragment */

            span->array->mask[i] = GL_FALSE;

            span->writeAll = GL_FALSE;

         }

      }

   }

}

/**

 * Execute the current fragment program for all the fragments

 * in the given span.

 */

void

_swrast_exec_fragment_program( struct gl_context *ctx, SWspan *span )

{

   const struct gl_fragment_program *program = ctx->FragmentProgram._Current;

   /* incoming colors should be floats */

   if (program->Base.InputsRead & FRAG_BIT_COL0) {

      ASSERT(span->array->ChanType == GL_FLOAT);

   }

   run_program(ctx, span, 0, span->end);

   if (program->Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_COLOR)) {

      span->interpMask &= ~SPAN_RGBA;

      span->arrayMask |= SPAN_RGBA;

   }

   if (program->Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {

      span->interpMask &= ~SPAN_Z;

      span->arrayMask |= SPAN_Z;

   }

}