/* * Copyright © 2016, 2019 Collabora, Ltd. * Copyright (c) 2018 DisplayLink (UK) Ltd. * * 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 (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 NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS 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. * * Author: Daniel Stone */ #include #include #include /** * Contains information about pixel formats, mapping format codes from * wl_shm and drm_fourcc.h (which are deliberately identical, but for the * special cases of WL_SHM_ARGB8888 and WL_SHM_XRGB8888) into various * sets of information. Helper functions are provided for dealing with these * raw structures. */ struct pixel_format_info { /** DRM/wl_shm format code */ uint32_t format; /** The DRM format name without the DRM_FORMAT_ prefix. */ const char *drm_format_name; /** If true, is only for internal use and should not be advertised to * clients to allow them to create buffers of this format. */ bool hide_from_clients; /** If non-zero, number of planes in base (non-modified) format. */ int num_planes; /** If format contains alpha channel, opaque equivalent of format, * i.e. alpha channel replaced with X. */ uint32_t opaque_substitute; /** How the format should be sampled, expressed in terms of tokens * from the EGL_WL_bind_wayland_display extension. If not set, * assumed to be either RGB or RGBA, depending on whether or not * the format contains an alpha channel. The samplers may still * return alpha even for opaque formats; users must manually set * the alpha channel to 1.0 (or ignore it) if the format is * opaque. */ uint32_t sampler_type; /** GL format, if data can be natively/directly uploaded. Note that * whilst DRM formats are little-endian unless explicitly specified, * (i.e. DRM_FORMAT_ARGB8888 is stored BGRA as sequential bytes in * memory), GL uses the sequential byte order, so that format maps to * GL_BGRA_EXT plus GL_UNSIGNED_BYTE. To add to the confusion, the * explicitly-sized types (e.g. GL_UNSIGNED_SHORT_5_5_5_1) read in * machine-endian order, so for these types, the correspondence * depends on endianness. */ int gl_format; /** GL data type, if data can be natively/directly uploaded. */ int gl_type; /** Pixman data type, if it agrees exactly with the wl_shm format */ pixman_format_code_t pixman_format; /** If set, this format can be used with the legacy drmModeAddFB() * function (not AddFB2), using this and the bpp member. */ int addfb_legacy_depth; /** Number of bits required to store a single pixel, for * single-planar formats. */ int bpp; /** Horizontal subsampling; if non-zero, divide the width by this * member to obtain the number of columns in the source buffer for * secondary planes only. Stride is not affected by horizontal * subsampling. */ int hsub; /** Vertical subsampling; if non-zero, divide the height by this * member to obtain the number of rows in the source buffer for * secondary planes only. */ int vsub; /* Ordering of chroma components. */ enum { ORDER_UV = 0, ORDER_VU, } chroma_order; /* If packed YUV (num_planes == 1), ordering of luma/chroma * components. */ enum { ORDER_LUMA_CHROMA = 0, ORDER_CHROMA_LUMA, } luma_chroma_order; /** How many significant bits each channel has, or zero if N/A. */ struct { int r; int g; int b; int a; } bits; /** How channel bits are interpreted, fixed (uint) or floating-point */ enum { PIXEL_COMPONENT_TYPE_FIXED = 0, PIXEL_COMPONENT_TYPE_FLOAT, } component_type; }; /** * Get pixel format information for a DRM format code * * Given a DRM format code, return a pixel format info structure describing * the properties of that format. * * @param format DRM format code to get info for * @returns A pixel format structure (must not be freed), or NULL if the * format could not be found */ const struct pixel_format_info * pixel_format_get_info(uint32_t format); /** * Get pixel format information for a SHM format code * * Given a SHM format code, return a DRM pixel format info structure describing * the properties of that format. * * @param format SHM format code to get info for. * @returns A pixel format structure (must not be freed), or NULL if the * format could not be found. */ const struct pixel_format_info * pixel_format_get_info_shm(uint32_t format); /** * Get pixel format information by table index * * Given a 0-based index in the format table, return the corresponding * DRM pixel format info structure. * * @param index Index of the pixel format in the table * @returns A pixel format structure (must not be freed), or NULL if the * index is out of range. */ const struct pixel_format_info * pixel_format_get_info_by_index(unsigned int index); /** * Return the size of the pixel format table * * @returns The number of entries in the pixel format table */ unsigned int pixel_format_get_info_count(void); /** * Get pixel format information for a named DRM format * * Given a DRM format name, return a pixel format info structure describing * the properties of that format. * * The DRM format name is the preprocessor token name from drm_fourcc.h * without the DRM_FORMAT_ prefix. The search is also case-insensitive. * Both "xrgb8888" and "XRGB8888" searches will find DRM_FORMAT_XRGB8888 * for example. * * @param drm_format_name DRM format name to get info for (not NULL) * @returns A pixel format structure (must not be freed), or NULL if the * name could not be found */ const struct pixel_format_info * pixel_format_get_info_by_drm_name(const char *drm_format_name); /** * Get pixel format information for a Pixman format code * * Given a Pixman format code, return a pixel format info structure describing * the properties of that format. * * @param pixman_format Pixman format code to get info for * @returns A pixel format structure (must not be freed), or NULL if the * format could not be found */ const struct pixel_format_info * pixel_format_get_info_by_pixman(pixman_format_code_t pixman_format); /** * Get number of planes used by a pixel format * * Given a pixel format info structure, return the number of planes * required for a buffer. Note that this is not necessarily identical to * the number of samplers required to be bound, as two views into a single * plane are sometimes required. * * @param format Pixel format info structure * @returns Number of planes required for the format */ unsigned int pixel_format_get_plane_count(const struct pixel_format_info *format); /** * Determine if a pixel format is opaque or contains alpha * * Returns whether or not the pixel format is opaque, or contains a * significant alpha channel. Note that the suggested EGL sampler type may * still sample undefined data into the alpha channel; users must consider * alpha as 1.0 if the format is opaque, and not rely on the sampler to * return this when sampling from the alpha channel. * * @param format Pixel format info structure * @returns True if the format is opaque, or false if it has significant alpha */ bool pixel_format_is_opaque(const struct pixel_format_info *format); /** * Get compatible opaque equivalent for a format * * Given a pixel format info structure, return a format which is wholly * compatible with the input format, but opaque, ignoring the alpha channel. * If an alpha format is provided, but the content is known to all be opaque, * then this can be used as a substitute to avoid blending. * * If the input format is opaque, this function will return the input format. * * @param format Pixel format info structure * @returns A pixel format info structure for the compatible opaque substitute */ const struct pixel_format_info * pixel_format_get_opaque_substitute(const struct pixel_format_info *format); /** * For an opaque format, get the equivalent format with alpha instead of an * ignored channel * * This is the opposite lookup from pixel_format_get_opaque_substitute(). * Finds the format whose opaque substitute is the given format. * * If the input format is not opaque or does not have ignored (X) bits, then * the search cannot find a match. * * @param format DRM format code to search for * @returns A pixel format info structure for the pixel format whose opaque * substitute is the argument, or NULL if no match. */ const struct pixel_format_info * pixel_format_get_info_by_opaque_substitute(uint32_t format); /** * Return the horizontal subsampling factor for a given plane * * When horizontal subsampling is effective, a sampler bound to a secondary * plane must bind the sampler with a smaller effective width. This function * returns the subsampling factor to use for the given plane. * * @param format Pixel format info structure * @param plane Zero-indexed plane number * @returns Horizontal subsampling factor for the given plane */ unsigned int pixel_format_hsub(const struct pixel_format_info *format, unsigned int plane); /** * Return the vertical subsampling factor for a given plane * * When vertical subsampling is effective, a sampler bound to a secondary * plane must bind the sampler with a smaller effective height. This function * returns the subsampling factor to use for the given plane. * * @param format Pixel format info structure * @param plane Zero-indexed plane number * @returns Vertical subsampling factor for the given plane */ unsigned int pixel_format_vsub(const struct pixel_format_info *format, unsigned int plane); /** * Return the effective sampling width for a given plane * * When horizontal subsampling is effective, a sampler bound to a secondary * plane must bind the sampler with a smaller effective width. This function * returns the effective width to use for the sampler, i.e. dividing by hsub. * * If horizontal subsampling is not in effect, this will be equal to the * width. * * @param format Pixel format info structure * @param plane Zero-indexed plane number * @param width Width of the buffer * @returns Effective width for sampling */ unsigned int pixel_format_width_for_plane(const struct pixel_format_info *format, unsigned int plane, unsigned int width); /** * Return the effective sampling height for a given plane * * When vertical subsampling is in effect, a sampler bound to a secondary * plane must bind the sampler with a smaller effective height. This function * returns the effective height to use for the sampler, i.e. dividing by vsub. * * If vertical subsampling is not in effect, this will be equal to the height. * * @param format Pixel format info structure * @param plane Zero-indexed plane number * @param height Height of the buffer * @returns Effective width for sampling */ unsigned int pixel_format_height_for_plane(const struct pixel_format_info *format, unsigned int plane, unsigned int height); /** * Return a human-readable format modifier. Comprised from the modifier name, * the vendor name, and the original encoded value in hexadecimal, using * 'VENDOR_NAME_MODIFIER_NAME (modifier_encoded_value)' pattern. In case the * modifier name (and the vendor name) isn't found, this returns the original * encoded value, as a string value. * * @param modifier the modifier in question * @returns a malloc'ed string, caller responsible for freeing after use. */ char * pixel_format_get_modifier(uint64_t modifier); /** * Return the wl_shm format code * * @param info Pixel format info structure * @returns The wl_shm format code for this pixel format. */ uint32_t pixel_format_get_shm_format(const struct pixel_format_info *info);