src/gallium/include/state_tracker/st_api.h

   1 /**********************************************************
   2  * Copyright 2010 VMware, Inc.  All rights reserved.
   3  *
   4  * Permission is hereby granted, free of charge, to any person
   5  * obtaining a copy of this software and associated documentation
   6  * files (the "Software"), to deal in the Software without
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   9  * of the Software, and to permit persons to whom the Software is
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  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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  25
  26
  27 #ifndef _ST_API_H_
  28 #define _ST_API_H_
  29
  30 #include "pipe/p_compiler.h"
  31 #include "pipe/p_format.h"
  32
  33 /**
  34  * \file API for communication between state trackers and state tracker
  35  * managers.
  36  *
  37  * While both are state tackers, we use the term state tracker for rendering
  38  * APIs such as OpenGL or OpenVG, and state tracker manager for window system
  39  * APIs such as EGL or GLX in this file.
  40  *
  41  * This file defines an API to be implemented by both state trackers and state
  42  * tracker managers.
  43  */
  44
  45 /**
  46  * The supported rendering API of a state tracker.
  47  */
  48 enum st_api_type {
  49    ST_API_OPENGL,
  50    ST_API_OPENGL_ES1,
  51    ST_API_OPENGL_ES2,
  52    ST_API_OPENVG,
  53
  54    ST_API_COUNT
  55 };
  56
  57 /**
  58  * Used in st_context_iface->teximage.
  59  */
  60 enum st_texture_type {
  61    ST_TEXTURE_1D,
  62    ST_TEXTURE_2D,
  63    ST_TEXTURE_3D,
  64    ST_TEXTURE_RECT,
  65 };
  66
  67 /**
  68  * Available attachments of framebuffer.
  69  */
  70 enum st_attachment_type {
  71    ST_ATTACHMENT_FRONT_LEFT,
  72    ST_ATTACHMENT_BACK_LEFT,
  73    ST_ATTACHMENT_FRONT_RIGHT,
  74    ST_ATTACHMENT_BACK_RIGHT,
  75    ST_ATTACHMENT_DEPTH_STENCIL,
  76    ST_ATTACHMENT_ACCUM,
  77    ST_ATTACHMENT_SAMPLE,
  78
  79    ST_ATTACHMENT_COUNT,
  80    ST_ATTACHMENT_INVALID = -1
  81 };
  82
  83 /* for buffer_mask in st_visual */
  84 #define ST_ATTACHMENT_FRONT_LEFT_MASK     (1 << ST_ATTACHMENT_FRONT_LEFT)
  85 #define ST_ATTACHMENT_BACK_LEFT_MASK      (1 << ST_ATTACHMENT_BACK_LEFT)
  86 #define ST_ATTACHMENT_FRONT_RIGHT_MASK    (1 << ST_ATTACHMENT_FRONT_RIGHT)
  87 #define ST_ATTACHMENT_BACK_RIGHT_MASK     (1 << ST_ATTACHMENT_BACK_RIGHT)
  88 #define ST_ATTACHMENT_DEPTH_STENCIL_MASK  (1 << ST_ATTACHMENT_DEPTH_STENCIL)
  89 #define ST_ATTACHMENT_ACCUM_MASK          (1 << ST_ATTACHMENT_ACCUM)
  90 #define ST_ATTACHMENT_SAMPLE_MASK         (1 << ST_ATTACHMENT_SAMPLE)
  91
  92 /**
  93  * Enumerations of state tracker context resources.
  94  */
  95 enum st_context_resource_type {
  96    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_2D,
  97    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_3D,
  98    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_CUBE_MAP_POSITIVE_X,
  99    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_CUBE_MAP_NEGATIVE_X,
 100    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_CUBE_MAP_POSITIVE_Y,
 101    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
 102    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_CUBE_MAP_POSITIVE_Z,
 103    ST_CONTEXT_RESOURCE_OPENGL_TEXTURE_CUBE_MAP_NEGATIVE_Z,
 104    ST_CONTEXT_RESOURCE_OPENGL_RENDERBUFFER,
 105    ST_CONTEXT_RESOURCE_OPENVG_PARENT_IMAGE,
 106 };
 107
 108 /**
 109  * The return type of st_api->get_proc_address.
 110  */
 111 typedef void (*st_proc_t)(void);
 112
 113 struct pipe_context;
 114 struct pipe_resource;
 115 struct pipe_fence_handle;
 116
 117 /**
 118  * Used in st_context_iface->get_resource_for_egl_image.
 119  */
 120 struct st_context_resource
 121 {
 122    /* these fields are filled by the caller */
 123    enum st_context_resource_type type;
 124    void *resource;
 125
 126    /* this is owned by the caller */
 127    struct pipe_resource *texture;
 128 };
 129
 130 /**
 131  * Used in st_manager_iface->get_egl_image.
 132  */
 133 struct st_egl_image
 134 {
 135    /* these fields are filled by the caller */
 136    struct st_context_iface *stctxi;
 137    void *egl_image;
 138
 139    /* this is owned by the caller */
 140    struct pipe_resource *texture;
 141
 142    unsigned face;
 143    unsigned level;
 144    unsigned zslice;
 145 };
 146
 147 /**
 148  * Represent the visual of a framebuffer.
 149  */
 150 struct st_visual
 151 {
 152    /**
 153     * Available buffers.  Tested with ST_FRAMEBUFFER_*_MASK.
 154     */
 155    unsigned buffer_mask;
 156
 157    /**
 158     * Buffer formats.  The formats are always set even when the buffer is
 159     * not available.
 160     */
 161    enum pipe_format color_format;
 162    enum pipe_format depth_stencil_format;
 163    enum pipe_format accum_format;
 164    int samples;
 165
 166    /**
 167     * Desired render buffer.
 168     */
 169    enum st_attachment_type render_buffer;
 170 };
 171
 172 /**
 173  * Represent a windowing system drawable.
 174  *
 175  * The framebuffer is implemented by the state tracker manager and
 176  * used by the state trackers.
 177  *
 178  * Instead of the winsys pokeing into the API context to figure
 179  * out what buffers that might be needed in the future by the API
 180  * context, it calls into the framebuffer to get the textures.
 181  *
 182  * This structure along with the notify_invalid_framebuffer
 183  * allows framebuffers to be shared between different threads
 184  * but at the same make the API context free from thread
 185  * syncronisation primitves, with the exception of a small
 186  * atomic flag used for notification of framebuffer dirty status.
 187  *
 188  * The thread syncronisation is put inside the framebuffer
 189  * and only called once the framebuffer has become dirty.
 190  */
 191 struct st_framebuffer_iface
 192 {
 193    /**
 194     * Available for the state tracker manager to use.
 195     */
 196    void *st_manager_private;
 197
 198    /**
 199     * The visual of a framebuffer.
 200     */
 201    const struct st_visual *visual;
 202
 203    /**
 204     * Flush the front buffer.
 205     *
 206     * On some window systems, changes to the front buffers are not immediately
 207     * visible.  They need to be flushed.
 208     *
 209     * @att is one of the front buffer attachments.
 210     */
 211    boolean (*flush_front)(struct st_framebuffer_iface *stfbi,
 212                           enum st_attachment_type statt);
 213
 214    /**
 215     * The state tracker asks for the textures it needs.
 216     *
 217     * It should try to only ask for attachments that it currently renders
 218     * to, thus allowing the winsys to delay the allocation of textures not
 219     * needed. For example front buffer attachments are not needed if you
 220     * only do back buffer rendering.
 221     *
 222     * The implementor of this function needs to also ensure
 223     * thread safty as this call might be done from multiple threads.
 224     *
 225     * The returned textures are owned by the caller.  They should be
 226     * unreferenced when no longer used.  If this function is called multiple
 227     * times with different sets of attachments, those buffers not included in
 228     * the last call might be destroyed.  This behavior might change in the
 229     * future.
 230     */
 231    boolean (*validate)(struct st_framebuffer_iface *stfbi,
 232                        const enum st_attachment_type *statts,
 233                        unsigned count,
 234                        struct pipe_resource **out);
 235 };
 236
 237 /**
 238  * Represent a rendering context.
 239  *
 240  * This entity is created from st_api and used by the state tracker manager.
 241  */
 242 struct st_context_iface
 243 {
 244    /**
 245     * Available for the state tracker and the manager to use.
 246     */
 247    void *st_context_private;
 248    void *st_manager_private;
 249
 250    /**
 251     * Destroy the context.
 252     */
 253    void (*destroy)(struct st_context_iface *stctxi);
 254
 255    /**
 256     * Invalidate the current textures that was taken from a framebuffer.
 257     *
 258     * The state tracker manager calls this function to let the rendering
 259     * context know that it should update the textures it got from
 260     * st_framebuffer_iface::validate.  It should do so at the latest time possible.
 261     * Possible right before sending triangles to the pipe context.
 262     *
 263     * For certain platforms this function might be called from a thread other
 264     * than the thread that the context is currently bound in, and must
 265     * therefore be thread safe. But it is the state tracker manager's
 266     * responsibility to make sure that the framebuffer is bound to the context
 267     * and the API context is current for the duration of this call.
 268     *
 269     * Thus reducing the sync primitive needed to a single atomic flag.
 270     */
 271    void (*notify_invalid_framebuffer)(struct st_context_iface *stctxi,
 272                                       struct st_framebuffer_iface *stfbi);
 273
 274    /**
 275     * Flush all drawing from context to the pipe also flushes the pipe.
 276     */
 277    void (*flush)(struct st_context_iface *stctxi, unsigned flags,
 278                  struct pipe_fence_handle **fence);
 279
 280    /**
 281     * Replace the texture image of a texture object at the specified level.
 282     *
 283     * This function is optional.
 284     */
 285    boolean (*teximage)(struct st_context_iface *stctxi, enum st_texture_type target,
 286                        int level, enum pipe_format internal_format,
 287                        struct pipe_resource *tex, boolean mipmap);
 288
 289    /**
 290     * Used to implement glXCopyContext.
 291     */
 292    void (*copy)(struct st_context_iface *stctxi,
 293                 struct st_context_iface *stsrci, unsigned mask);
 294
 295    /**
 296     * Look up and return the info of a resource for EGLImage.
 297     *
 298     * This function is optional.
 299     */
 300    boolean (*get_resource_for_egl_image)(struct st_context_iface *stctxi,
 301                                          struct st_context_resource *stres);
 302 };
 303
 304
 305 /**
 306  * Represent a state tracker manager.
 307  *
 308  * This interface is implemented by the state tracker manager.  It corresponds
 309  * to a "display" in the window system.
 310  */
 311 struct st_manager
 312 {
 313    struct pipe_screen *screen;
 314
 315    /**
 316     * Look up and return the info of an EGLImage.
 317     *
 318     * This function is optional.
 319     */
 320    boolean (*get_egl_image)(struct st_manager *smapi,
 321                             struct st_egl_image *stimg);
 322 };
 323
 324 /**
 325  * Represent a rendering API such as OpenGL or OpenVG.
 326  *
 327  * Implemented by the state tracker and used by the state tracker manager.
 328  */
 329 struct st_api
 330 {
 331    /**
 332     * Destroy the API.
 333     */
 334    void (*destroy)(struct st_api *stapi);
 335
 336    /**
 337     * Return an API entry point.
 338     *
 339     * For GL this is the same as _glapi_get_proc_address.
 340     */
 341    st_proc_t (*get_proc_address)(struct st_api *stapi, const char *procname);
 342
 343    /**
 344     * Return true if the visual is supported by the state tracker.
 345     */
 346    boolean (*is_visual_supported)(struct st_api *stapi,
 347                                   const struct st_visual *visual);
 348
 349    /**
 350     * Create a rendering context.
 351     */
 352    struct st_context_iface *(*create_context)(struct st_api *stapi,
 353                                               struct st_manager *smapi,
 354                                               const struct st_visual *visual,
 355                                               struct st_context_iface *stsharei);
 356
 357    /**
 358     * Bind the context to the calling thread with draw and read as drawables.
 359     *
 360     * The framebuffers might have different visuals than the context does.
 361     */
 362    boolean (*make_current)(struct st_api *stapi,
 363                            struct st_context_iface *stctxi,
 364                            struct st_framebuffer_iface *stdrawi,
 365                            struct st_framebuffer_iface *streadi);
 366
 367    /**
 368     * Get the currently bound context in the calling thread.
 369     */
 370    struct st_context_iface *(*get_current)(struct st_api *stapi);
 371 };
 372
 373 /**
 374  * Return true if the visual has the specified buffers.
 375  */
 376 static INLINE boolean
 377 st_visual_have_buffers(const struct st_visual *visual, unsigned mask)
 378 {
 379    return ((visual->buffer_mask & mask) == mask);
 380 }
 381
 382 /* these symbols may need to be dynamically lookup up */
 383 extern PUBLIC struct st_api * st_api_create_OpenGL(void);
 384 extern PUBLIC struct st_api * st_api_create_OpenGL_ES1(void);
 385 extern PUBLIC struct st_api * st_api_create_OpenGL_ES2(void);
 386 extern PUBLIC struct st_api * st_api_create_OpenVG(void);
 387
 388 /**
 389  * The entry points of the state trackers.
 390  */
 391 #define ST_CREATE_OPENGL_SYMBOL      "st_api_create_OpenGL"
 392 #define ST_CREATE_OPENGL_ES1_SYMBOL  "st_api_create_OpenGL_ES1"
 393 #define ST_CREATE_OPENGL_ES2_SYMBOL  "st_api_create_OpenGL_ES2"
 394 #define ST_CREATE_OPENVG_SYMBOL      "st_api_create_OpenVG"
 395
 396 #endif /* _ST_API_H_ */