text: /**************************************************************************
   * 
   * Copyright 2007 VMware, Inc.
   * 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 VMWARE 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 <keithw@vmware.com>
    *   Brian Paul
    */
   
  
  #include "main/macros.h"
  #include "main/mtypes.h"
  #include "main/glformats.h"
  #include "main/samplerobj.h"
  #include "main/teximage.h"
  #include "main/texobj.h"
  
  #include "st_context.h"
  #include "st_cb_texture.h"
  #include "st_format.h"
  #include "st_atom.h"
  #include "st_sampler_view.h"
  #include "st_texture.h"
  #include "pipe/p_context.h"
  #include "pipe/p_defines.h"
  
  #include "cso_cache/cso_context.h"
  
  #include "util/format/u_format.h"
  
  
  /**
   * Convert GLenum texcoord wrap tokens to pipe tokens.
   */
  static GLuint
  gl_wrap_xlate(GLenum wrap)
  {
     /* Take advantage of how the enums are defined. */
     static const unsigned table[32] = {
        [GL_REPEAT & 0x1f] = PIPE_TEX_WRAP_REPEAT,
        [GL_CLAMP & 0x1f] = PIPE_TEX_WRAP_CLAMP,
        [GL_CLAMP_TO_EDGE & 0x1f] = PIPE_TEX_WRAP_CLAMP_TO_EDGE,
        [GL_CLAMP_TO_BORDER & 0x1f] = PIPE_TEX_WRAP_CLAMP_TO_BORDER,
        [GL_MIRRORED_REPEAT & 0x1f] = PIPE_TEX_WRAP_MIRROR_REPEAT,
        [GL_MIRROR_CLAMP_EXT & 0x1f] = PIPE_TEX_WRAP_MIRROR_CLAMP,
        [GL_MIRROR_CLAMP_TO_EDGE & 0x1f] = PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE,
        [GL_MIRROR_CLAMP_TO_BORDER_EXT & 0x1f] = PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER,
     };
  
     return table[wrap & 0x1f];
  }
  
  
  static GLuint
  gl_filter_to_mip_filter(GLenum filter)
  {
     /* Take advantage of how the enums are defined. */
     if (filter <= GL_LINEAR)
        return PIPE_TEX_MIPFILTER_NONE;
     if (filter <= GL_LINEAR_MIPMAP_NEAREST)
        return PIPE_TEX_MIPFILTER_NEAREST;
  
     return PIPE_TEX_MIPFILTER_LINEAR;
  }
  
  
  static GLuint
  gl_filter_to_img_filter(GLenum filter)
  {
     /* Take advantage of how the enums are defined. */
     if (filter & 1)
        return PIPE_TEX_FILTER_LINEAR;
  
     return PIPE_TEX_FILTER_NEAREST;
  }
  
  
  /**
   * Convert a gl_sampler_object to a pipe_sampler_state object.
   */
  void
  st_convert_sampler(const struct st_context *st,
                     const struct gl_texture_object *texobj,
                     const struct gl_sampler_object *msamp,
                     float tex_unit_lod_bias,
                     struct pipe_sampler_state *sampler)
  {
     memset(sampler, 0, sizeof(*sampler));
     sampler->wrap_s = gl_wrap_xlate(msamp->WrapS);
     sampler->wrap_t = gl_wrap_xlate(msamp->WrapT);
     sampler->wrap_r = gl_wrap_xlate(msamp->WrapR);
  
     sampler->min_img_filter = gl_filter_to_img_filter(msamp->MinFilter);
     sampler->min_mip_filter = gl_filter_to_mip_filter(msamp->MinFilter);
     sampler->mag_img_filter = gl_filter_to_img_filter(msamp->MagFilter);
  
     if (texobj->Target != GL_TEXTURE_RECTANGLE_ARB)
        sampler->normalized_coords = 1;
  
     sampler->lod_bias = msamp->LodBias + tex_unit_lod_bias;
     /* Reduce the number of states by allowing only the values that AMD GCN
      * can represent. Apps use lod_bias for smooth transitions to bigger mipmap
      * levels.
      */
     sampler->lod_bias = CLAMP(sampler->lod_bias, -16, 16);
     sampler->lod_bias = floorf(sampler->lod_bias * 256) / 256;
  
     sampler->min_lod = MAX2(msamp->MinLod, 0.0f);
     sampler->max_lod = msamp->MaxLod;
     if (sampler->max_lod < sampler->min_lod) {
        /* The GL spec doesn't seem to specify what to do in this case.
         * Swap the values.
         */
        float tmp = sampler->max_lod;
        sampler->max_lod = sampler->min_lod;
        sampler->min_lod = tmp;
        assert(sampler->min_lod <= sampler->max_lod);
     }
  
     /* Check that only wrap modes using the border color have the first bit
      * set.
      */
     STATIC_ASSERT(PIPE_TEX_WRAP_CLAMP & 0x1);
     STATIC_ASSERT(PIPE_TEX_WRAP_CLAMP_TO_BORDER & 0x1);
     STATIC_ASSERT(PIPE_TEX_WRAP_MIRROR_CLAMP & 0x1);
     STATIC_ASSERT(PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER & 0x1);
     STATIC_ASSERT(((PIPE_TEX_WRAP_REPEAT |
                     PIPE_TEX_WRAP_CLAMP_TO_EDGE |
                     PIPE_TEX_WRAP_MIRROR_REPEAT |
                     PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE) & 0x1) == 0);
  
     /* For non-black borders... */
     if (/* This is true if wrap modes are using the border color: */
         (sampler->wrap_s | sampler->wrap_t | sampler->wrap_r) & 0x1 &&
         (msamp->BorderColor.ui[0] ||
          msamp->BorderColor.ui[1] ||
          msamp->BorderColor.ui[2] ||
          msamp->BorderColor.ui[3])) {
        const GLboolean is_integer = texobj->_IsIntegerFormat;
        GLenum texBaseFormat = _mesa_base_tex_image(texobj)->_BaseFormat;
  
        if (texobj->StencilSampling)
           texBaseFormat = GL_STENCIL_INDEX;
  
        if (st->apply_texture_swizzle_to_border_color) {
           const struct st_texture_object *stobj = st_texture_object_const(texobj);
           /* XXX: clean that up to not use the sampler view at all */
           const struct st_sampler_view *sv = st_texture_get_current_sampler_view(st, stobj);
  
           if (sv) {
              struct pipe_sampler_view *view = sv->view;
              union pipe_color_union tmp;
              const unsigned char swz[4] =
              {
                 view->swizzle_r,
                 view->swizzle_g,
                 view->swizzle_b,
                 view->swizzle_a,
              };
  
              st_translate_color(&msamp->BorderColor, &tmp,
                                 texBaseFormat, is_integer);
  
              util_format_apply_color_swizzle(&sampler->border_color,
                                              &tmp, swz, is_integer);
           } else {
              st_translate_color(&msamp->BorderColor,
                                 &sampler->border_color,
                                 texBaseFormat, is_integer);
           }
        } else {
           st_translate_color(&msamp->BorderColor,
                              &sampler->border_color,
                              texBaseFormat, is_integer);
        }
     }
  
     sampler->max_anisotropy = (msamp->MaxAnisotropy == 1.0 ?
                                0 : (GLuint) msamp->MaxAnisotropy);
  
     /* If sampling a depth texture and using shadow comparison */
     if (msamp->CompareMode == GL_COMPARE_R_TO_TEXTURE) {
        GLenum texBaseFormat = _mesa_base_tex_image(texobj)->_BaseFormat;
  
        if (texBaseFormat == GL_DEPTH_COMPONENT ||
            (texBaseFormat == GL_DEPTH_STENCIL && !texobj->StencilSampling)) {
           sampler->compare_mode = PIPE_TEX_COMPARE_R_TO_TEXTURE;
           sampler->compare_func = st_compare_func_to_pipe(msamp->CompareFunc);
        }
     }
  
     /* Only set the seamless cube map texture parameter because the per-context
      * enable should be ignored and treated as disabled when using texture
      * handles, as specified by ARB_bindless_texture.
      */
     sampler->seamless_cube_map = msamp->CubeMapSeamless;
  }
  
  /**
   * Get a pipe_sampler_state object from a texture unit.
   */
  void
  st_convert_sampler_from_unit(const struct st_context *st,
                               struct pipe_sampler_state *sampler,
                               GLuint texUnit)
  {
     const struct gl_texture_object *texobj;
     struct gl_context *ctx = st->ctx;
     const struct gl_sampler_object *msamp;
  
     texobj = ctx->Texture.Unit[texUnit]._Current;
     assert(texobj);
     assert(texobj->Target != GL_TEXTURE_BUFFER);
  
     msamp = _mesa_get_samplerobj(ctx, texUnit);
  
     st_convert_sampler(st, texobj, msamp, ctx->Texture.Unit[texUnit].LodBias,
                        sampler);
  
     sampler->seamless_cube_map |= ctx->Texture.CubeMapSeamless;
  }
  
  
  /**
   * Update the gallium driver's sampler state for fragment, vertex or
   * geometry shader stage.
   */
  static void
  update_shader_samplers(struct st_context *st,
                         enum pipe_shader_type shader_stage,
                         const struct gl_program *prog,
                         struct pipe_sampler_state *samplers,
                         unsigned *out_num_samplers)
  {
     struct gl_context *ctx = st->ctx;
     GLbitfield samplers_used = prog->SamplersUsed;
     GLbitfield free_slots = ~prog->SamplersUsed;
     GLbitfield external_samplers_used = prog->ExternalSamplersUsed;
     unsigned unit, num_samplers;
     struct pipe_sampler_state local_samplers[PIPE_MAX_SAMPLERS];
     const struct pipe_sampler_state *states[PIPE_MAX_SAMPLERS];
  
     if (samplers_used == 0x0) {
        if (out_num_samplers)
           *out_num_samplers = 0;
        return;
     }
  
     if (!samplers)
        samplers = local_samplers;
  
     num_samplers = util_last_bit(samplers_used);
  
     /* loop over sampler units (aka tex image units) */
     for (unit = 0; samplers_used; unit++, samplers_used >>= 1) {
        struct pipe_sampler_state *sampler = samplers + unit;
        unsigned tex_unit = prog->SamplerUnits[unit];
  
        /* Don't update the sampler for TBOs. cso_context will not bind sampler
         * states that are NULL.
         */
        if (samplers_used & 1 &&
            ctx->Texture.Unit[tex_unit]._Current->Target != GL_TEXTURE_BUFFER) {
           st_convert_sampler_from_unit(st, sampler, tex_unit);
           states[unit] = sampler;
        } else {
           states[unit] = NULL;
        }
     }
  
     /* For any external samplers with multiplaner YUV, stuff the additional
      * sampler states we need at the end.
      *
      * Just re-use the existing sampler-state from the primary slot.
      */
     while (unlikely(external_samplers_used)) {
        GLuint unit = u_bit_scan(&external_samplers_used);
        GLuint extra = 0;
        struct st_texture_object *stObj =
              st_get_texture_object(st->ctx, prog, unit);
        struct pipe_sampler_state *sampler = samplers + unit;
  
        /* if resource format matches then YUV wasn't lowered */
        if (!stObj || st_get_view_format(stObj) == stObj->pt->format)
           continue;
  
        switch (st_get_view_format(stObj)) {
        case PIPE_FORMAT_NV12:
        case PIPE_FORMAT_P010:
        case PIPE_FORMAT_P016:
        case PIPE_FORMAT_YUYV:
        case PIPE_FORMAT_UYVY:
           /* we need one additional sampler: */
           extra = u_bit_scan(&free_slots);
           states[extra] = sampler;
           break;
        case PIPE_FORMAT_IYUV:
           /* we need two additional samplers: */
           extra = u_bit_scan(&free_slots);
           states[extra] = sampler;
           extra = u_bit_scan(&free_slots);
           states[extra] = sampler;
           break;
        default:
           break;
        }
  
        num_samplers = MAX2(num_samplers, extra + 1);
     }
  
     cso_set_samplers(st->cso_context, shader_stage, num_samplers, states);
  
     if (out_num_samplers)
        *out_num_samplers = num_samplers;
  }
  
  
  void
  st_update_vertex_samplers(struct st_context *st)
  {
     const struct gl_context *ctx = st->ctx;
  
     update_shader_samplers(st,
                            PIPE_SHADER_VERTEX,
                            ctx->VertexProgram._Current,
                            st->state.vert_samplers,
                            &st->state.num_vert_samplers);
  }
  
  
  void
  st_update_tessctrl_samplers(struct st_context *st)
  {
     const struct gl_context *ctx = st->ctx;
  
     if (ctx->TessCtrlProgram._Current) {
        update_shader_samplers(st,
                               PIPE_SHADER_TESS_CTRL,
                               ctx->TessCtrlProgram._Current, NULL, NULL);
     }
  }
  
  
  void
  st_update_tesseval_samplers(struct st_context *st)
  {
     const struct gl_context *ctx = st->ctx;
  
     if (ctx->TessEvalProgram._Current) {
        update_shader_samplers(st,
                               PIPE_SHADER_TESS_EVAL,
                               ctx->TessEvalProgram._Current, NULL, NULL);
     }
  }
  
  
  void
  st_update_geometry_samplers(struct st_context *st)
  {
     const struct gl_context *ctx = st->ctx;
  
     if (ctx->GeometryProgram._Current) {
        update_shader_samplers(st,
                               PIPE_SHADER_GEOMETRY,
                               ctx->GeometryProgram._Current, NULL, NULL);
     }
  }
  
  
  void
  st_update_fragment_samplers(struct st_context *st)
  {
     const struct gl_context *ctx = st->ctx;
  
     update_shader_samplers(st,
                            PIPE_SHADER_FRAGMENT,
                            ctx->FragmentProgram._Current,
                            st->state.frag_samplers,
                            &st->state.num_frag_samplers);
  }
  
  
  void
  st_update_compute_samplers(struct st_context *st)
  {
     const struct gl_context *ctx = st->ctx;
  
     if (ctx->ComputeProgram._Current) {
        update_shader_samplers(st,
                               PIPE_SHADER_COMPUTE,
                               ctx->ComputeProgram._Current, NULL, NULL);
     }
  }
  