[libretro] new RETRO_ENVIRONMENT_SET_GEOMETRY callback is now being used instead of RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO when screen width/height change

libretro/libretro.c

@@ -482,7 +482,7 @@ static bool update_viewport(void)
       vheight = vheight * 2;
    }
 
-   return (oh != vheight);
+   return ((ow != vwidth) || (oh != vheight));
 }
 
 static void check_variables(void)
@@ -1099,7 +1099,7 @@ void retro_run(void)
       {
          struct retro_system_av_info info;
          retro_get_system_av_info(&info);
-         environ_cb(RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO, &info);
+         environ_cb(RETRO_ENVIRONMENT_SET_GEOMETRY, &info.geometry);
       }
    }
 

libretro/libretro.h

@@ -388,16 +388,11 @@ enum retro_mod
                                            // It can be used by the frontend to potentially warn
                                            // about too demanding implementations.
                                            //
-                                           // The levels are "floating", but roughly defined as:
+                                           // The levels are "floating".
-                                           // 0: Low-powered embedded devices such as Raspberry Pi
-                                           // 1: 6th generation consoles, such as Wii/Xbox 1, and phones, tablets, etc.
-                                           // 2: 7th generation consoles, such as PS3/360, with sub-par CPUs.
-                                           // 3: Modern desktop/laptops with reasonably powerful CPUs.
-                                           // 4: High-end desktops with very powerful CPUs.
                                            //
                                            // This function can be called on a per-game basis,
                                            // as certain games an implementation can play might be
-                                           // particularily demanding.
+                                           // particularly demanding.
                                            // If called, it should be called in retro_load_game().
                                            //
 #define RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY 9
@@ -589,15 +584,15 @@ enum retro_mod
                                            // This should *only* be used if the core is completely altering the internal resolutions, aspect ratios, timings, sampling rate, etc.
                                            // Calling this can require a full reinitialization of video/audio drivers in the frontend,
                                            // so it is important to call it very sparingly, and usually only with the users explicit consent.
-                                           // An eventual driver reinit will happen so that video and audio callbacks
+                                           // An eventual driver reinitialize will happen so that video and audio callbacks
                                            // happening after this call within the same retro_run() call will target the newly initialized driver.
                                            //
                                            // This callback makes it possible to support configurable resolutions in games, which can be useful to
                                            // avoid setting the "worst case" in max_width/max_height.
                                            //
                                            // ***HIGHLY RECOMMENDED*** Do not call this callback every time resolution changes in an emulator core if it's
-                                           // expected to be a temporary change, for the reasons of possible driver reinit.
+                                           // expected to be a temporary change, for the reasons of possible driver reinitialization.
-                                           // This call is not a free pass for not trying to provide correct values in retro_get_system_av_info().
+                                           // This call is not a free pass for not trying to provide correct values in retro_get_system_av_info(). If you need to change things like aspect ratio or nominal width/height, use RETRO_ENVIRONMENT_SET_GEOMETRY, which is a softer variant of SET_SYSTEM_AV_INFO.
                                            //
                                            // If this returns false, the frontend does not acknowledge a changed av_info struct.
 #define RETRO_ENVIRONMENT_SET_PROC_ADDRESS_CALLBACK 33
@@ -640,6 +635,129 @@ enum retro_mod
                                            // The core must pass an array of const struct retro_controller_info which is terminated with
                                            // a blanked out struct. Each element of the struct corresponds to an ascending port index to retro_set_controller_port_device().
                                            // Even if special device types are set in the libretro core, libretro should only poll input based on the base input device types.
+#define RETRO_ENVIRONMENT_SET_MEMORY_MAPS (36 | RETRO_ENVIRONMENT_EXPERIMENTAL)
+                                           // const struct retro_memory_map * --
+                                           // This environment call lets a libretro core tell the frontend about the memory maps this
+                                           // core emulates. This can be used to implement, for example, cheats in a core-agnostic way.
+                                           //
+                                           // Should only be used by emulators; it doesn't make much sense for anything else.
+                                           // It is recommended to expose all relevant pointers through retro_get_memory_* as well.
+                                           //
+                                           // Can be called from retro_init and retro_load_game.
+                                           //
+#define RETRO_ENVIRONMENT_SET_GEOMETRY 37
+                                           // const struct retro_game_geometry * --
+                                           // This environment call is similar to SET_SYSTEM_AV_INFO for changing video parameters,
+                                           // but provides a guarantee that drivers will not be reinitialized.
+                                           // This can only be called from within retro_run().
+                                           //
+                                           // The purpose of this call is to allow a core to alter nominal width/heights as well as aspect ratios on-the-fly,
+                                           // which can be useful for some emulators to change in run-time.
+                                           //
+                                           // max_width/max_height arguments are ignored and cannot be changed
+                                           // with this call as this could potentially require a reinitialization or a non-constant time operation.
+                                           // If max_width/max_height are to be changed, SET_SYSTEM_AV_INFO is required.
+                                           //
+                                           // A frontend must guarantee that this environment call completes in constant time.
+
+
+
+
+#define RETRO_MEMDESC_CONST     (1 << 0)   // The frontend will never change this memory area once retro_load_game has returned.
+#define RETRO_MEMDESC_BIGENDIAN (1 << 1)   // The memory area contains big endian data. Default is little endian.
+#define RETRO_MEMDESC_ALIGN_2   (1 << 16)  // All memory access in this area is aligned to their own size, or 2, whichever is smaller.
+#define RETRO_MEMDESC_ALIGN_4   (2 << 16)
+#define RETRO_MEMDESC_ALIGN_8   (3 << 16)
+#define RETRO_MEMDESC_MINSIZE_2 (1 << 24)  // All memory in this region is accessed at least 2 bytes at the time.
+#define RETRO_MEMDESC_MINSIZE_4 (2 << 24)
+#define RETRO_MEMDESC_MINSIZE_8 (3 << 24)
+struct retro_memory_descriptor
+{
+   uint64_t flags;
+
+   // Pointer to the start of the relevant ROM or RAM chip.
+   // It's strongly recommended to use 'offset' if possible, rather than doing math on the pointer.
+   // If the same byte is mapped my multiple descriptors, their descriptors must have the same pointer.
+   // If 'start' does not point to the first byte in the pointer, put the difference in 'offset' instead.
+   // May be NULL if there's nothing usable here (e.g. hardware registers and open bus). No flags should be set if the pointer is NULL.
+   // It's recommended to minimize the number of descriptors if possible, but not mandatory.
+   void *ptr;
+   size_t offset;
+
+   // This is the location in the emulated address space where the mapping starts.
+   size_t start;
+
+   // Which bits must be same as in 'start' for this mapping to apply.
+   // The first memory descriptor to claim a certain byte is the one that applies.
+   // A bit which is set in 'start' must also be set in this.
+   // Can be zero, in which case each byte is assumed mapped exactly once. In this case, 'len' must be a power of two.
+   size_t select;
+
+   // If this is nonzero, the set bits are assumed not connected to the memory chip's address pins.
+   size_t disconnect;
+
+   // This one tells the size of the current memory area.
+   // If, after start+disconnect are applied, the address is higher than this, the highest bit of the address is cleared.
+   // If the address is still too high, the next highest bit is cleared.
+   // Can be zero, in which case it's assumed to be infinite (as limited by 'select' and 'disconnect').
+   size_t len;
+
+   // To go from emulated address to physical address, the following order applies:
+   // Subtract 'start', pick off 'disconnect', apply 'len', add 'offset'.
+
+   // The address space name must consist of only a-zA-Z0-9_-, should be as short as feasible (maximum length is 8 plus the NUL),
+   // and may not be any other address space plus one or more 0-9A-F at the end.
+   // However, multiple memory descriptors for the same address space is allowed, and the address
+   // space name can be empty. NULL is treated as empty.
+   // Address space names are case sensitive, but avoid lowercase if possible.
+   // The same pointer may exist in multiple address spaces.
+   // Examples:
+   // blank+blank - valid (multiple things may be mapped in the same namespace)
+   // 'Sp'+'Sp' - valid (multiple things may be mapped in the same namespace)
+   // 'A'+'B' - valid (neither is a prefix of each other)
+   // 'S'+blank - valid ('S' is not in 0-9A-F)
+   // 'a'+blank - valid ('a' is not in 0-9A-F)
+   // 'a'+'A' - valid (neither is a prefix of each other)
+   // 'AR'+blank - valid ('R' is not in 0-9A-F)
+   // 'ARB'+blank - valid (the B can't be part of the address either, because there is no namespace 'AR')
+   // blank+'B' - not valid, because it's ambigous which address space B1234 would refer to.
+   //  The length can't be used for that purpose; the frontend may want to append arbitrary data to an address, without a separator.
+   const char *addrspace;
+};
+// The frontend may use the largest value of 'start'+'select' in a certain namespace to infer the size of the address space.
+// If the address space is larger than that, a mapping with .ptr=NULL should be at the end of the array, with .select set to all ones for as long as the address space is big.
+// Sample descriptors (minus .ptr, and RETRO_MEMFLAG_ on the flags):
+// SNES WRAM:
+// .start=0x7E0000, .len=0x20000
+// (Note that this must be mapped before the ROM in most cases; some of the ROM mappers try to claim $7E0000, or at least $7E8000.)
+// SNES SPC700 RAM:
+// .addrspace="S", .len=0x10000
+// SNES WRAM mirrors:
+// .flags=MIRROR, .start=0x000000, .select=0xC0E000, .len=0x2000
+// .flags=MIRROR, .start=0x800000, .select=0xC0E000, .len=0x2000
+// SNES WRAM mirrors, alternate equivalent descriptor:
+// .flags=MIRROR, .select=0x40E000, .disconnect=~0x1FFF
+// (Various similar constructions can be created by combining parts of the above two.)
+// SNES LoROM (512KB, mirrored a couple of times):
+// .flags=CONST, .start=0x008000, .select=0x408000, .disconnect=0x8000, .len=512*1024
+// .flags=CONST, .start=0x400000, .select=0x400000, .disconnect=0x8000, .len=512*1024
+// SNES HiROM (4MB):
+// .flags=CONST,                 .start=0x400000, .select=0x400000, .len=4*1024*1024
+// .flags=CONST, .offset=0x8000, .start=0x008000, .select=0x408000, .len=4*1024*1024
+// SNES ExHiROM (8MB):
+// .flags=CONST, .offset=0,                  .start=0xC00000, .select=0xC00000, .len=4*1024*1024
+// .flags=CONST, .offset=4*1024*1024,        .start=0x400000, .select=0xC00000, .len=4*1024*1024
+// .flags=CONST, .offset=0x8000,             .start=0x808000, .select=0xC08000, .len=4*1024*1024
+// .flags=CONST, .offset=4*1024*1024+0x8000, .start=0x008000, .select=0xC08000, .len=4*1024*1024
+// Clarify the size of the address space:
+// .ptr=NULL, .select=0xFFFFFF
+// .len can be implied by .select in many of them, but was included for clarity.
+
+struct retro_memory_map
+{
+   const struct retro_memory_descriptor *descriptors;
+   unsigned num_descriptors;
+};
 
 struct retro_controller_description
 {
@@ -987,7 +1105,7 @@ struct retro_frame_time_callback
 // it should implement context_destroy callback.
 // If called, all GPU resources must be reinitialized.
 // Usually called when frontend reinits video driver.
-// Also called first time video driver is initialized, allowing libretro core to init resources.
+// Also called first time video driver is initialized, allowing libretro core to initialize resources.
 typedef void (*retro_hw_context_reset_t)(void);
 // Gets current framebuffer which is to be rendered to. Could change every frame potentially.
 typedef uintptr_t (*retro_hw_get_current_framebuffer_t)(void);
@@ -998,10 +1116,11 @@ typedef retro_proc_address_t (*retro_hw_get_proc_address_t)(const char *sym);
 enum retro_hw_context_type
 {
    RETRO_HW_CONTEXT_NONE             = 0,
-   RETRO_HW_CONTEXT_OPENGL, // OpenGL 2.x. Latest version available before 3.x+. Driver can choose to use latest compatibility context.
+   RETRO_HW_CONTEXT_OPENGL           = 1, // OpenGL 2.x. Driver can choose to use latest compatibility context.
-   RETRO_HW_CONTEXT_OPENGLES2, // GLES 2.0
+   RETRO_HW_CONTEXT_OPENGLES2        = 2, // GLES 2.0
-   RETRO_HW_CONTEXT_OPENGL_CORE, // Modern desktop core GL context. Use major/minor fields to set GL version.
+   RETRO_HW_CONTEXT_OPENGL_CORE      = 3, // Modern desktop core GL context. Use version_major/version_minor fields to set GL version.
-   RETRO_HW_CONTEXT_OPENGLES3, // GLES 3.0
+   RETRO_HW_CONTEXT_OPENGLES3        = 4, // GLES 3.0
+   RETRO_HW_CONTEXT_OPENGLES_VERSION = 5, // GLES 3.1+. Set version_major/version_minor. For GLES2 and GLES3, use the corresponding enums directly.
 
    RETRO_HW_CONTEXT_DUMMY = INT_MAX
 };
@@ -1026,8 +1145,8 @@ struct retro_hw_render_callback
    bool stencil; // Set if stencil buffers should be attached.
    // If depth and stencil are true, a packed 24/8 buffer will be added. Only attaching stencil is invalid and will be ignored.
    bool bottom_left_origin; // Use conventional bottom-left origin convention. Is false, standard libretro top-left origin semantics are used.
-   unsigned version_major; // Major version number for core GL context.
+   unsigned version_major; // Major version number for core GL context or GLES 3.1+.
-   unsigned version_minor; // Minor version number for core GL context.
+   unsigned version_minor; // Minor version number for core GL context or GLES 3.1+.
 
    bool cache_context; // If this is true, the frontend will go very far to avoid resetting context in scenarios like toggling fullscreen, etc.
    // The reset callback might still be called in extreme situations such as if the context is lost beyond recovery.