src/gallium/drivers/softpipe/sp_screen.c - platform/external/mesa3d - Git at Google

 /**************************************************************************
  *
  * Copyright 2008 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 "util/u_memory.h"
 #include "util/u_format.h"
 #include "util/u_format_s3tc.h"
 #include "util/u_video.h"
 #include "os/os_time.h"
 #include "pipe/p_defines.h"
 #include "pipe/p_screen.h"
 #include "draw/draw_context.h"
 #include "vl/vl_decoder.h"
 #include "vl/vl_video_buffer.h"

 #include "state_tracker/sw_winsys.h"
 #include "tgsi/tgsi_exec.h"

 #include "sp_texture.h"
 #include "sp_screen.h"
 #include "sp_context.h"
 #include "sp_fence.h"
 #include "sp_public.h"

 DEBUG_GET_ONCE_BOOL_OPTION(use_llvm, "SOFTPIPE_USE_LLVM", FALSE)

 static const char *
 softpipe_get_vendor(struct pipe_screen *screen)
 {
    return "VMware, Inc.";
 }


 static const char *
 softpipe_get_name(struct pipe_screen *screen)
 {
    return "softpipe";
 }


 static int
 softpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
 {
    switch (param) {
    case PIPE_CAP_MAX_COMBINED_SAMPLERS:
       return 2 * PIPE_MAX_SAMPLERS;  /* VS + FS */
    case PIPE_CAP_NPOT_TEXTURES:
       return 1;
    case PIPE_CAP_TWO_SIDED_STENCIL:
       return 1;
    case PIPE_CAP_SM3:
       return 1;
    case PIPE_CAP_ANISOTROPIC_FILTER:
       return 1;
    case PIPE_CAP_POINT_SPRITE:
       return 1;
    case PIPE_CAP_MAX_RENDER_TARGETS:
       return PIPE_MAX_COLOR_BUFS;
    case PIPE_CAP_MAX_DUAL_SOURCE_RENDER_TARGETS:
       return 1;
    case PIPE_CAP_OCCLUSION_QUERY:
       return 1;
    case PIPE_CAP_TIMER_QUERY:
       return 1;
    case PIPE_CAP_TEXTURE_MIRROR_CLAMP:
       return 1;
    case PIPE_CAP_TEXTURE_SHADOW_MAP:
       return 1;
    case PIPE_CAP_TEXTURE_SWIZZLE:
       return 1;
    case PIPE_CAP_MAX_TEXTURE_2D_LEVELS:
       return SP_MAX_TEXTURE_2D_LEVELS;
    case PIPE_CAP_MAX_TEXTURE_3D_LEVELS:
       return SP_MAX_TEXTURE_3D_LEVELS;
    case PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS:
       return SP_MAX_TEXTURE_CUBE_LEVELS;
    case PIPE_CAP_BLEND_EQUATION_SEPARATE:
       return 1;
    case PIPE_CAP_INDEP_BLEND_ENABLE:
       return 1;
    case PIPE_CAP_INDEP_BLEND_FUNC:
       return 1;
    case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
    case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
    case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
    case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
       return 1;
    case PIPE_CAP_DEPTH_CLIP_DISABLE:
       return 0;
    case PIPE_CAP_MAX_STREAM_OUTPUT_BUFFERS:
       return PIPE_MAX_SO_BUFFERS;
    case PIPE_CAP_MAX_STREAM_OUTPUT_SEPARATE_COMPONENTS:
    case PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS:
       return 16*4;
    case PIPE_CAP_PRIMITIVE_RESTART:
       return 1;
    case PIPE_CAP_DEPTHSTENCIL_CLEAR_SEPARATE:
       return 0;
    case PIPE_CAP_SHADER_STENCIL_EXPORT:
       return 1;
    case PIPE_CAP_TGSI_INSTANCEID:
    case PIPE_CAP_VERTEX_ELEMENT_INSTANCE_DIVISOR:
       return 1;
    case PIPE_CAP_SEAMLESS_CUBE_MAP:
    case PIPE_CAP_SEAMLESS_CUBE_MAP_PER_TEXTURE:
       return 0;
    case PIPE_CAP_SCALED_RESOLVE:
       return 0;
    case PIPE_CAP_MAX_TEXTURE_ARRAY_LAYERS:
       return 256; /* for GL3 */
    case PIPE_CAP_MIN_TEXEL_OFFSET:
       return -8;
    case PIPE_CAP_MAX_TEXEL_OFFSET:
       return 7;
    case PIPE_CAP_CONDITIONAL_RENDER:
       return 1;
    case PIPE_CAP_TEXTURE_BARRIER:
       return 0;
    case PIPE_CAP_FRAGMENT_COLOR_CLAMPED:
    case PIPE_CAP_VERTEX_COLOR_UNCLAMPED: /* draw module */
    case PIPE_CAP_VERTEX_COLOR_CLAMPED: /* draw module */
       return 1;
    case PIPE_CAP_MIXED_COLORBUFFER_FORMATS:
       return 0;
    case PIPE_CAP_GLSL_FEATURE_LEVEL:
       return 130;
    case PIPE_CAP_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION:
       return 0;
    case PIPE_CAP_COMPUTE:
       return 0;
    case PIPE_CAP_USER_VERTEX_BUFFERS:
    case PIPE_CAP_USER_INDEX_BUFFERS:
    case PIPE_CAP_USER_CONSTANT_BUFFERS:
       return 1;
    case PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT:
       return 16;
    case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
    case PIPE_CAP_TGSI_CAN_COMPACT_VARYINGS:
    case PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS:
    case PIPE_CAP_VERTEX_BUFFER_OFFSET_4BYTE_ALIGNED_ONLY:
    case PIPE_CAP_VERTEX_BUFFER_STRIDE_4BYTE_ALIGNED_ONLY:
    case PIPE_CAP_VERTEX_ELEMENT_SRC_OFFSET_4BYTE_ALIGNED_ONLY:
    case PIPE_CAP_START_INSTANCE:
       return 0;
    case PIPE_CAP_QUERY_TIMESTAMP:
       return 1;
    }
    /* should only get here on unhandled cases */
    debug_printf("Unexpected PIPE_CAP %d query\n", param);
    return 0;
 }

 static int
 softpipe_get_shader_param(struct pipe_screen *screen, unsigned shader, enum pipe_shader_cap param)
 {
    struct softpipe_screen *sp_screen = softpipe_screen(screen);
    switch(shader)
    {
    case PIPE_SHADER_FRAGMENT:
       return tgsi_exec_get_shader_param(param);
    case PIPE_SHADER_VERTEX:
    case PIPE_SHADER_GEOMETRY:
       switch (param) {
       case PIPE_SHADER_CAP_MAX_TEXTURE_SAMPLERS:
          if (sp_screen->use_llvm)
             /* Softpipe doesn't yet know how to tell draw/llvm about textures */
             return 0;
 	 else
             return PIPE_MAX_SAMPLERS;
       default:
 	 if (sp_screen->use_llvm)
             return draw_get_shader_param(shader, param);
          else
             return draw_get_shader_param_no_llvm(shader, param);
       }
    default:
       return 0;
    }
 }

 static float
 softpipe_get_paramf(struct pipe_screen *screen, enum pipe_capf param)
 {
    switch (param) {
    case PIPE_CAPF_MAX_LINE_WIDTH:
       /* fall-through */
    case PIPE_CAPF_MAX_LINE_WIDTH_AA:
       return 255.0; /* arbitrary */
    case PIPE_CAPF_MAX_POINT_WIDTH:
       /* fall-through */
    case PIPE_CAPF_MAX_POINT_WIDTH_AA:
       return 255.0; /* arbitrary */
    case PIPE_CAPF_MAX_TEXTURE_ANISOTROPY:
       return 16.0;
    case PIPE_CAPF_MAX_TEXTURE_LOD_BIAS:
       return 16.0; /* arbitrary */
    case PIPE_CAPF_GUARD_BAND_LEFT:
    case PIPE_CAPF_GUARD_BAND_TOP:
    case PIPE_CAPF_GUARD_BAND_RIGHT:
    case PIPE_CAPF_GUARD_BAND_BOTTOM:
       return 0.0;
    }
    /* should only get here on unhandled cases */
    debug_printf("Unexpected PIPE_CAPF %d query\n", param);
    return 0.0;
 }

 static int
 softpipe_get_video_param(struct pipe_screen *screen,
                          enum pipe_video_profile profile,
                          enum pipe_video_cap param)
 {
    switch (param) {
    case PIPE_VIDEO_CAP_SUPPORTED:
        return vl_profile_supported(screen, profile);
    case PIPE_VIDEO_CAP_NPOT_TEXTURES:
       return 0;
    case PIPE_VIDEO_CAP_MAX_WIDTH:
    case PIPE_VIDEO_CAP_MAX_HEIGHT:
       return vl_video_buffer_max_size(screen);
    case PIPE_VIDEO_CAP_PREFERED_FORMAT:
       return PIPE_FORMAT_NV12;
    case PIPE_VIDEO_CAP_PREFERS_INTERLACED:
       return false;
    case PIPE_VIDEO_CAP_SUPPORTS_INTERLACED:
       return false;
    case PIPE_VIDEO_CAP_SUPPORTS_PROGRESSIVE:
       return true;
    default:
       return 0;
    }
 }

 /**
  * Query format support for creating a texture, drawing surface, etc.
  * \param format  the format to test
  * \param type  one of PIPE_TEXTURE, PIPE_SURFACE
  */
 static boolean
 softpipe_is_format_supported( struct pipe_screen *screen,
                               enum pipe_format format,
                               enum pipe_texture_target target,
                               unsigned sample_count,
                               unsigned bind)
 {
    struct sw_winsys *winsys = softpipe_screen(screen)->winsys;
    const struct util_format_description *format_desc;

    assert(target == PIPE_BUFFER ||
           target == PIPE_TEXTURE_1D ||
           target == PIPE_TEXTURE_1D_ARRAY ||
           target == PIPE_TEXTURE_2D ||
           target == PIPE_TEXTURE_2D_ARRAY ||
           target == PIPE_TEXTURE_RECT ||
           target == PIPE_TEXTURE_3D ||
           target == PIPE_TEXTURE_CUBE);

    format_desc = util_format_description(format);
    if (!format_desc)
       return FALSE;

    if (sample_count > 1)
       return FALSE;

    if (bind & (PIPE_BIND_DISPLAY_TARGET |
                PIPE_BIND_SCANOUT |
                PIPE_BIND_SHARED)) {
       if(!winsys->is_displaytarget_format_supported(winsys, bind, format))
          return FALSE;
    }

    if (bind & PIPE_BIND_RENDER_TARGET) {
       if (format_desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS)
          return FALSE;

       /*
        * Although possible, it is unnatural to render into compressed or YUV
        * surfaces. So disable these here to avoid going into weird paths
        * inside the state trackers.
        */
       if (format_desc->block.width != 1 ||
           format_desc->block.height != 1)
          return FALSE;
    }

    if (bind & PIPE_BIND_DEPTH_STENCIL) {
       if (format_desc->colorspace != UTIL_FORMAT_COLORSPACE_ZS)
          return FALSE;
    }

    /*
     * All other operations (sampling, transfer, etc).
     */

    if (format_desc->layout == UTIL_FORMAT_LAYOUT_S3TC) {
       return util_format_s3tc_enabled;
    }

    /*
     * Everything else should be supported by u_format.
     */
    return TRUE;
 }


 static void
 softpipe_destroy_screen( struct pipe_screen *screen )
 {
    struct softpipe_screen *sp_screen = softpipe_screen(screen);
    struct sw_winsys *winsys = sp_screen->winsys;

    if(winsys->destroy)
       winsys->destroy(winsys);

    FREE(screen);
 }


 /* This is often overriden by the co-state tracker.
  */
 static void
 softpipe_flush_frontbuffer(struct pipe_screen *_screen,
                            struct pipe_resource *resource,
                            unsigned level, unsigned layer,
                            void *context_private)
 {
    struct softpipe_screen *screen = softpipe_screen(_screen);
    struct sw_winsys *winsys = screen->winsys;
    struct softpipe_resource *texture = softpipe_resource(resource);

    assert(texture->dt);
    if (texture->dt)
       winsys->displaytarget_display(winsys, texture->dt, context_private);
 }

 static uint64_t
 softpipe_get_timestamp(struct pipe_screen *_screen)
 {
    return os_time_get()*1000;
 }

 /**
  * Create a new pipe_screen object
  * Note: we're not presently subclassing pipe_screen (no softpipe_screen).
  */
 struct pipe_screen *
 softpipe_create_screen(struct sw_winsys *winsys)
 {
    struct softpipe_screen *screen = CALLOC_STRUCT(softpipe_screen);

    if (!screen)
       return NULL;

    screen->winsys = winsys;

    screen->base.destroy = softpipe_destroy_screen;

    screen->base.get_name = softpipe_get_name;
    screen->base.get_vendor = softpipe_get_vendor;
    screen->base.get_param = softpipe_get_param;
    screen->base.get_shader_param = softpipe_get_shader_param;
    screen->base.get_paramf = softpipe_get_paramf;
    screen->base.get_video_param = softpipe_get_video_param;
    screen->base.get_timestamp = softpipe_get_timestamp;
    screen->base.is_format_supported = softpipe_is_format_supported;
    screen->base.is_video_format_supported = vl_video_buffer_is_format_supported;
    screen->base.context_create = softpipe_create_context;
    screen->base.flush_frontbuffer = softpipe_flush_frontbuffer;

    screen->use_llvm = debug_get_option_use_llvm();

    util_format_s3tc_init();

    softpipe_init_screen_texture_funcs(&screen->base);
    softpipe_init_screen_fence_funcs(&screen->base);

    return &screen->base;
 }
	/**************************************************************************
	*
	* Copyright 2008 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 "util/u_memory.h"
	#include "util/u_format.h"
	#include "util/u_format_s3tc.h"
	#include "util/u_video.h"
	#include "os/os_time.h"
	#include "pipe/p_defines.h"
	#include "pipe/p_screen.h"
	#include "draw/draw_context.h"
	#include "vl/vl_decoder.h"
	#include "vl/vl_video_buffer.h"

	#include "state_tracker/sw_winsys.h"
	#include "tgsi/tgsi_exec.h"

	#include "sp_texture.h"
	#include "sp_screen.h"
	#include "sp_context.h"
	#include "sp_fence.h"
	#include "sp_public.h"

	DEBUG_GET_ONCE_BOOL_OPTION(use_llvm, "SOFTPIPE_USE_LLVM", FALSE)

	static const char *
	softpipe_get_vendor(struct pipe_screen *screen)
	{
	return "VMware, Inc.";
	}


	static const char *
	softpipe_get_name(struct pipe_screen *screen)
	{
	return "softpipe";
	}


	static int
	softpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
	{
	switch (param) {
	case PIPE_CAP_MAX_COMBINED_SAMPLERS:
	return 2 * PIPE_MAX_SAMPLERS; /* VS + FS */
	case PIPE_CAP_NPOT_TEXTURES:
	return 1;
	case PIPE_CAP_TWO_SIDED_STENCIL:
	return 1;
	case PIPE_CAP_SM3:
	return 1;
	case PIPE_CAP_ANISOTROPIC_FILTER:
	return 1;
	case PIPE_CAP_POINT_SPRITE:
	return 1;
	case PIPE_CAP_MAX_RENDER_TARGETS:
	return PIPE_MAX_COLOR_BUFS;
	case PIPE_CAP_MAX_DUAL_SOURCE_RENDER_TARGETS:
	return 1;
	case PIPE_CAP_OCCLUSION_QUERY:
	return 1;
	case PIPE_CAP_TIMER_QUERY:
	return 1;
	case PIPE_CAP_TEXTURE_MIRROR_CLAMP:
	return 1;
	case PIPE_CAP_TEXTURE_SHADOW_MAP:
	return 1;
	case PIPE_CAP_TEXTURE_SWIZZLE:
	return 1;
	case PIPE_CAP_MAX_TEXTURE_2D_LEVELS:
	return SP_MAX_TEXTURE_2D_LEVELS;
	case PIPE_CAP_MAX_TEXTURE_3D_LEVELS:
	return SP_MAX_TEXTURE_3D_LEVELS;
	case PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS:
	return SP_MAX_TEXTURE_CUBE_LEVELS;
	case PIPE_CAP_BLEND_EQUATION_SEPARATE:
	return 1;
	case PIPE_CAP_INDEP_BLEND_ENABLE:
	return 1;
	case PIPE_CAP_INDEP_BLEND_FUNC:
	return 1;
	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
	return 1;
	case PIPE_CAP_DEPTH_CLIP_DISABLE:
	return 0;
	case PIPE_CAP_MAX_STREAM_OUTPUT_BUFFERS:
	return PIPE_MAX_SO_BUFFERS;
	case PIPE_CAP_MAX_STREAM_OUTPUT_SEPARATE_COMPONENTS:
	case PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS:
	return 16*4;
	case PIPE_CAP_PRIMITIVE_RESTART:
	return 1;
	case PIPE_CAP_DEPTHSTENCIL_CLEAR_SEPARATE:
	return 0;
	case PIPE_CAP_SHADER_STENCIL_EXPORT:
	return 1;
	case PIPE_CAP_TGSI_INSTANCEID:
	case PIPE_CAP_VERTEX_ELEMENT_INSTANCE_DIVISOR:
	return 1;
	case PIPE_CAP_SEAMLESS_CUBE_MAP:
	case PIPE_CAP_SEAMLESS_CUBE_MAP_PER_TEXTURE:
	return 0;
	case PIPE_CAP_SCALED_RESOLVE:
	return 0;
	case PIPE_CAP_MAX_TEXTURE_ARRAY_LAYERS:
	return 256; /* for GL3 */
	case PIPE_CAP_MIN_TEXEL_OFFSET:
	return -8;
	case PIPE_CAP_MAX_TEXEL_OFFSET:
	return 7;
	case PIPE_CAP_CONDITIONAL_RENDER:
	return 1;
	case PIPE_CAP_TEXTURE_BARRIER:
	return 0;
	case PIPE_CAP_FRAGMENT_COLOR_CLAMPED:
	case PIPE_CAP_VERTEX_COLOR_UNCLAMPED: /* draw module */
	case PIPE_CAP_VERTEX_COLOR_CLAMPED: /* draw module */
	return 1;
	case PIPE_CAP_MIXED_COLORBUFFER_FORMATS:
	return 0;
	case PIPE_CAP_GLSL_FEATURE_LEVEL:
	return 130;
	case PIPE_CAP_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION:
	return 0;
	case PIPE_CAP_COMPUTE:
	return 0;
	case PIPE_CAP_USER_VERTEX_BUFFERS:
	case PIPE_CAP_USER_INDEX_BUFFERS:
	case PIPE_CAP_USER_CONSTANT_BUFFERS:
	return 1;
	case PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT:
	return 16;
	case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
	case PIPE_CAP_TGSI_CAN_COMPACT_VARYINGS:
	case PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS:
	case PIPE_CAP_VERTEX_BUFFER_OFFSET_4BYTE_ALIGNED_ONLY:
	case PIPE_CAP_VERTEX_BUFFER_STRIDE_4BYTE_ALIGNED_ONLY:
	case PIPE_CAP_VERTEX_ELEMENT_SRC_OFFSET_4BYTE_ALIGNED_ONLY:
	case PIPE_CAP_START_INSTANCE:
	return 0;
	case PIPE_CAP_QUERY_TIMESTAMP:
	return 1;
	}
	/* should only get here on unhandled cases */
	debug_printf("Unexpected PIPE_CAP %d query\n", param);
	return 0;
	}

	static int
	softpipe_get_shader_param(struct pipe_screen *screen, unsigned shader, enum pipe_shader_cap param)
	{
	struct softpipe_screen *sp_screen = softpipe_screen(screen);
	switch(shader)
	{
	case PIPE_SHADER_FRAGMENT:
	return tgsi_exec_get_shader_param(param);
	case PIPE_SHADER_VERTEX:
	case PIPE_SHADER_GEOMETRY:
	switch (param) {
	case PIPE_SHADER_CAP_MAX_TEXTURE_SAMPLERS:
	if (sp_screen->use_llvm)
	/* Softpipe doesn't yet know how to tell draw/llvm about textures */
	return 0;
	else
	return PIPE_MAX_SAMPLERS;
	default:
	if (sp_screen->use_llvm)
	return draw_get_shader_param(shader, param);
	else
	return draw_get_shader_param_no_llvm(shader, param);
	}
	default:
	return 0;
	}
	}

	static float
	softpipe_get_paramf(struct pipe_screen *screen, enum pipe_capf param)
	{
	switch (param) {
	case PIPE_CAPF_MAX_LINE_WIDTH:
	/* fall-through */
	case PIPE_CAPF_MAX_LINE_WIDTH_AA:
	return 255.0; /* arbitrary */
	case PIPE_CAPF_MAX_POINT_WIDTH:
	/* fall-through */
	case PIPE_CAPF_MAX_POINT_WIDTH_AA:
	return 255.0; /* arbitrary */
	case PIPE_CAPF_MAX_TEXTURE_ANISOTROPY:
	return 16.0;
	case PIPE_CAPF_MAX_TEXTURE_LOD_BIAS:
	return 16.0; /* arbitrary */
	case PIPE_CAPF_GUARD_BAND_LEFT:
	case PIPE_CAPF_GUARD_BAND_TOP:
	case PIPE_CAPF_GUARD_BAND_RIGHT:
	case PIPE_CAPF_GUARD_BAND_BOTTOM:
	return 0.0;
	}
	/* should only get here on unhandled cases */
	debug_printf("Unexpected PIPE_CAPF %d query\n", param);
	return 0.0;
	}

	static int
	softpipe_get_video_param(struct pipe_screen *screen,
	enum pipe_video_profile profile,
	enum pipe_video_cap param)
	{
	switch (param) {
	case PIPE_VIDEO_CAP_SUPPORTED:
	return vl_profile_supported(screen, profile);
	case PIPE_VIDEO_CAP_NPOT_TEXTURES:
	return 0;
	case PIPE_VIDEO_CAP_MAX_WIDTH:
	case PIPE_VIDEO_CAP_MAX_HEIGHT:
	return vl_video_buffer_max_size(screen);
	case PIPE_VIDEO_CAP_PREFERED_FORMAT:
	return PIPE_FORMAT_NV12;
	case PIPE_VIDEO_CAP_PREFERS_INTERLACED:
	return false;
	case PIPE_VIDEO_CAP_SUPPORTS_INTERLACED:
	return false;
	case PIPE_VIDEO_CAP_SUPPORTS_PROGRESSIVE:
	return true;
	default:
	return 0;
	}
	}

	/**
	* Query format support for creating a texture, drawing surface, etc.
	* \param format the format to test
	* \param type one of PIPE_TEXTURE, PIPE_SURFACE
	*/
	static boolean
	softpipe_is_format_supported( struct pipe_screen *screen,
	enum pipe_format format,
	enum pipe_texture_target target,
	unsigned sample_count,
	unsigned bind)
	{
	struct sw_winsys *winsys = softpipe_screen(screen)->winsys;
	const struct util_format_description *format_desc;

	assert(target == PIPE_BUFFER \|\|
	target == PIPE_TEXTURE_1D \|\|
	target == PIPE_TEXTURE_1D_ARRAY \|\|
	target == PIPE_TEXTURE_2D \|\|
	target == PIPE_TEXTURE_2D_ARRAY \|\|
	target == PIPE_TEXTURE_RECT \|\|
	target == PIPE_TEXTURE_3D \|\|
	target == PIPE_TEXTURE_CUBE);

	format_desc = util_format_description(format);
	if (!format_desc)
	return FALSE;

	if (sample_count > 1)
	return FALSE;

	if (bind & (PIPE_BIND_DISPLAY_TARGET \|
	PIPE_BIND_SCANOUT \|
	PIPE_BIND_SHARED)) {
	if(!winsys->is_displaytarget_format_supported(winsys, bind, format))
	return FALSE;
	}

	if (bind & PIPE_BIND_RENDER_TARGET) {
	if (format_desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS)
	return FALSE;

	/*
	* Although possible, it is unnatural to render into compressed or YUV
	* surfaces. So disable these here to avoid going into weird paths
	* inside the state trackers.
	*/
	if (format_desc->block.width != 1 \|\|
	format_desc->block.height != 1)
	return FALSE;
	}

	if (bind & PIPE_BIND_DEPTH_STENCIL) {
	if (format_desc->colorspace != UTIL_FORMAT_COLORSPACE_ZS)
	return FALSE;
	}

	/*
	* All other operations (sampling, transfer, etc).
	*/

	if (format_desc->layout == UTIL_FORMAT_LAYOUT_S3TC) {
	return util_format_s3tc_enabled;
	}

	/*
	* Everything else should be supported by u_format.
	*/
	return TRUE;
	}


	static void
	softpipe_destroy_screen( struct pipe_screen *screen )
	{
	struct softpipe_screen *sp_screen = softpipe_screen(screen);
	struct sw_winsys *winsys = sp_screen->winsys;

	if(winsys->destroy)
	winsys->destroy(winsys);

	FREE(screen);
	}


	/* This is often overriden by the co-state tracker.
	*/
	static void
	softpipe_flush_frontbuffer(struct pipe_screen *_screen,
	struct pipe_resource *resource,
	unsigned level, unsigned layer,
	void *context_private)
	{
	struct softpipe_screen *screen = softpipe_screen(_screen);
	struct sw_winsys *winsys = screen->winsys;
	struct softpipe_resource *texture = softpipe_resource(resource);

	assert(texture->dt);
	if (texture->dt)
	winsys->displaytarget_display(winsys, texture->dt, context_private);
	}

	static uint64_t
	softpipe_get_timestamp(struct pipe_screen *_screen)
	{
	return os_time_get()*1000;
	}

	/**
	* Create a new pipe_screen object
	* Note: we're not presently subclassing pipe_screen (no softpipe_screen).
	*/
	struct pipe_screen *
	softpipe_create_screen(struct sw_winsys *winsys)
	{
	struct softpipe_screen *screen = CALLOC_STRUCT(softpipe_screen);

	if (!screen)
	return NULL;

	screen->winsys = winsys;

	screen->base.destroy = softpipe_destroy_screen;

	screen->base.get_name = softpipe_get_name;
	screen->base.get_vendor = softpipe_get_vendor;
	screen->base.get_param = softpipe_get_param;
	screen->base.get_shader_param = softpipe_get_shader_param;
	screen->base.get_paramf = softpipe_get_paramf;
	screen->base.get_video_param = softpipe_get_video_param;
	screen->base.get_timestamp = softpipe_get_timestamp;
	screen->base.is_format_supported = softpipe_is_format_supported;
	screen->base.is_video_format_supported = vl_video_buffer_is_format_supported;
	screen->base.context_create = softpipe_create_context;
	screen->base.flush_frontbuffer = softpipe_flush_frontbuffer;

	screen->use_llvm = debug_get_option_use_llvm();

	util_format_s3tc_init();

	softpipe_init_screen_texture_funcs(&screen->base);
	softpipe_init_screen_fence_funcs(&screen->base);

	return &screen->base;
	}