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Unverified Commit 8133b0a0 authored by jdgleaver's avatar jdgleaver Committed by GitHub
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Fix frame pacing (#100)

parent 5145f79b
Pipeline #101923 passed with stages
in 8 minutes and 33 seconds
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libretro/libretro.cpp
View file @ 8133b0a0
......@@ -7,6 +7,11 @@
#include "handy.h"
#ifdef _3DS
extern "C" void* linearMemAlign(size_t size, size_t alignment);
extern "C" void linearFree(void* mem);
#endif
static retro_log_printf_t log_cb;
static retro_video_refresh_t video_cb;
static retro_audio_sample_batch_t audio_batch_cb;
......@@ -20,14 +25,31 @@ static int16_t *soundBuffer = NULL;
#define RETRO_LYNX_WIDTH 160
#define RETRO_LYNX_HEIGHT 102
#define RETRO_LYNX_FPS 75.0
/* Note: Set 75Hz here to reflect the nominal
* maximum of the Lynx hardware; actual 'core
* options' default is 60Hz */
static uint16_t retro_refresh_rate = 75;
static ULONG retro_cycles_per_frame = (HANDY_SYSTEM_FREQ / 75);
static bool retro_refresh_rate_updated = false;
// core options
static uint8_t lynx_rot = MIKIE_NO_ROTATE;
static uint8_t lynx_width = RETRO_LYNX_WIDTH;
static uint8_t lynx_height = RETRO_LYNX_HEIGHT;
static uint8_t lynx_rot = MIKIE_NO_ROTATE;
static uint8_t lynx_width = RETRO_LYNX_WIDTH;
static uint8_t lynx_height = RETRO_LYNX_HEIGHT;
static uint8_t lynx_width_next = RETRO_LYNX_WIDTH;
static uint8_t lynx_height_next = RETRO_LYNX_HEIGHT;
static bool lynx_rot_updated = false;
typedef enum
{
ROTATION_PENDING_NONE = 0,
ROTATION_PENDING_CORE,
ROTATION_PENDING_FRONTEND
} lynx_rotation_pending_t;
static lynx_rotation_pending_t lynx_rotation_pending = ROTATION_PENDING_NONE;
bool lynx_rotation_button_down = false;
static int RETRO_PIX_BYTES = 2;
#if defined(FRONTEND_SUPPORTS_RGB565)
......@@ -36,10 +58,11 @@ static int RETRO_PIX_DEPTH = 16;
static int RETRO_PIX_DEPTH = 15;
#endif
static uint8_t framebuffer[RETRO_LYNX_WIDTH*RETRO_LYNX_WIDTH*4];
static uint8_t *framebuffer = NULL;
static bool newFrame = false;
static bool initialized = false;
static bool frame_available = false;
static bool initialized = false;
static bool video_out_enabled = false;
struct map { unsigned retro; unsigned lynx; };
......@@ -132,19 +155,22 @@ static void init_frameskip(void)
{
/* Frameskip is enabled - increase frontend
* audio latency to minimise potential
* buffer underruns */
float frame_time_msec = 1000.0f / (float)RETRO_LYNX_FPS;
/* Set latency to 8x current frame time...
* (for 60Hz cores we normally use a 6x
* multiplier - but the Lynx runs
* at an unusually high frame rate, which
* seems to place greater demands on the
* frontend. Increasing the multiplier to
* 8x gives the frontend more room to
* manoeuvre, and improves the efficacy of
* the 'Auto' frameskip setting) */
audio_latency = (unsigned)((8.0f * frame_time_msec) + 0.5f);
* buffer underruns
* > Note: The core can run at a variety of
* (frontend) display refresh rates, and
* internally frames can be generated at
* any rate from 0 to 75Hz (possibly 79Hz).
* This makes it difficult to determine
* an appropriate audio latency level; for
* simplicity, assume that we are running
* at the default display refresh rate of
* 60Hz (ultimately this will translate to
* a latency of 128ms, which should be
* sufficient in all cases) */
float frame_time_msec = 1000.0f / 60.0f;
/* Set latency to 6x current frame time */
audio_latency = (unsigned)((6.0f * frame_time_msec) + 0.5f);
/* ...then round up to nearest multiple of 32 */
audio_latency = (audio_latency + 0x1F) & ~0x1F;
......@@ -251,96 +277,153 @@ unsigned retro_api_version(void)
static void update_geometry(void)
{
struct retro_system_av_info info;
retro_get_system_av_info(&info);
environ_cb(RETRO_ENVIRONMENT_SET_GEOMETRY, &info);
}
static void update_timing(void)
{
struct retro_system_av_info info;
retro_get_system_av_info(&info);
environ_cb(RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO, &info);
}
static void lynx_rotate(void);
static UBYTE* lynx_display_callback(ULONG objref)
{
int total;
if(!initialized)
if(!video_out_enabled)
return (UBYTE*)framebuffer;
video_cb((bool)gSkipFrame ? NULL : framebuffer,
lynx_width, lynx_height, RETRO_LYNX_WIDTH*RETRO_PIX_BYTES);
/* lynx_display_callback() may be called multiple
* times per retro_run(). Ensure that video_cb()
* is only called once per retro_run(). */
if (!frame_available)
{
/* Check whether current frame has a different
* rotation from the previous one; if so,
* notify the frontend before drawing it */
if (!gSkipFrame &&
(lynx_rotation_pending == ROTATION_PENDING_FRONTEND))
{
lynx_rotation_pending = ROTATION_PENDING_NONE;
lynx_width = lynx_width_next;
lynx_height = lynx_height_next;
update_geometry();
}
video_cb((bool)gSkipFrame ? NULL : framebuffer,
lynx_width, lynx_height,
RETRO_LYNX_WIDTH * RETRO_PIX_BYTES);
/* Divide gAudioBufferPointer by number of channels */
audio_batch_cb(soundBuffer, gAudioBufferPointer >> 1);
gAudioBufferPointer = 0;
/* Check whether the next frame should be
* rendered with a change in rotation */
if (lynx_rotation_pending == ROTATION_PENDING_CORE)
{
lynx_rotation_pending = ROTATION_PENDING_FRONTEND;
/* An annoyance: lynx_rotate() ends up calling
* lynx_display_callback(), so to avoid infinite
* circular recursion we must temporarily disable
* lynx_display_callback()... */
video_out_enabled = false;
lynx_rotate();
video_out_enabled = true;
}
newFrame = true;
frame_available = true;
/* Must unset gSkipFrame here since the next
* frame may be (partially) drawn before the
* current retro_run() returns, and we will not
* know if this frame is needed until the *next*
* call of retro_run()... */
gSkipFrame = 0;
}
return (UBYTE*)framebuffer;
}
static void lynx_rotate(void)
{
if(!lynx)
if (!lynx)
return;
switch(lynx_rot)
switch (lynx_rot)
{
default:
lynx_rot = MIKIE_NO_ROTATE;
// intentional fall-through
case MIKIE_NO_ROTATE:
lynx_width = RETRO_LYNX_WIDTH;
lynx_height = RETRO_LYNX_HEIGHT;
btn_map = btn_map_no_rot;
lynx_width_next = RETRO_LYNX_WIDTH;
lynx_height_next = RETRO_LYNX_HEIGHT;
btn_map = btn_map_no_rot;
break;
case MIKIE_ROTATE_R:
lynx_width = RETRO_LYNX_HEIGHT;
lynx_height = RETRO_LYNX_WIDTH;
btn_map = btn_map_rot_90;
lynx_width_next = RETRO_LYNX_HEIGHT;
lynx_height_next = RETRO_LYNX_WIDTH;
btn_map = btn_map_rot_90;
break;
case MIKIE_ROTATE_L:
lynx_width = RETRO_LYNX_HEIGHT;
lynx_height = RETRO_LYNX_WIDTH;
btn_map = btn_map_rot_270;
lynx_width_next = RETRO_LYNX_HEIGHT;
lynx_height_next = RETRO_LYNX_WIDTH;
btn_map = btn_map_rot_270;
break;
}
switch (RETRO_PIX_DEPTH)
{
case 15:
lynx->DisplaySetAttributes(lynx_rot, MIKIE_PIXEL_FORMAT_16BPP_555, RETRO_LYNX_WIDTH*2, lynx_display_callback, (ULONG)0);
lynx->DisplaySetAttributes(lynx_rot,
MIKIE_PIXEL_FORMAT_16BPP_555,
RETRO_LYNX_WIDTH * 2,
lynx_display_callback, (ULONG)0);
break;
#if defined(ABGR1555)
case 16:
lynx->DisplaySetAttributes(lynx_rot, MIKIE_PIXEL_FORMAT_16BPP_BGR555, RETRO_LYNX_WIDTH*2, lynx_display_callback, (ULONG)0);
lynx->DisplaySetAttributes(lynx_rot,
MIKIE_PIXEL_FORMAT_16BPP_BGR555,
RETRO_LYNX_WIDTH * 2,
lynx_display_callback, (ULONG)0);
break;
#else
case 16:
lynx->DisplaySetAttributes(lynx_rot, MIKIE_PIXEL_FORMAT_16BPP_565, RETRO_LYNX_WIDTH*2, lynx_display_callback, (ULONG)0);
lynx->DisplaySetAttributes(lynx_rot,
MIKIE_PIXEL_FORMAT_16BPP_565,
RETRO_LYNX_WIDTH * 2,
lynx_display_callback, (ULONG)0);
break;
#endif
case 24:
lynx->DisplaySetAttributes(lynx_rot, MIKIE_PIXEL_FORMAT_32BPP, RETRO_LYNX_WIDTH*4, lynx_display_callback, (ULONG)0);
lynx->DisplaySetAttributes(lynx_rot,
MIKIE_PIXEL_FORMAT_32BPP,
RETRO_LYNX_WIDTH * 4,
lynx_display_callback, (ULONG)0);
break;
default:
lynx->DisplaySetAttributes(lynx_rot, MIKIE_PIXEL_FORMAT_32BPP, RETRO_LYNX_WIDTH*4, lynx_display_callback, (ULONG)0);
lynx->DisplaySetAttributes(lynx_rot,
MIKIE_PIXEL_FORMAT_32BPP,
RETRO_LYNX_WIDTH * 4,
lynx_display_callback, (ULONG)0);
break;
}
update_geometry();
lynx_rot_updated = true;
}
static void check_variables(void)
{
struct retro_variable var = {0};
unsigned old_lynx_rot;
unsigned old_frameskip_type;
uint16_t old_retro_refresh_rate;
var.key = "handy_rot";
var.value = NULL;
if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value) {
unsigned old_rotate = lynx_rot;
old_lynx_rot = lynx_rot;
lynx_rot = MIKIE_NO_ROTATE;
var.key = "handy_rot";
var.value = NULL;
if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
{
if (strcmp(var.value, "None") == 0)
lynx_rot = MIKIE_NO_ROTATE;
else if (strcmp(var.value, "90") == 0)
......@@ -348,8 +431,9 @@ static void check_variables(void)
else if (strcmp(var.value, "270") == 0)
lynx_rot = MIKIE_ROTATE_L;
if (old_rotate != lynx_rot)
lynx_rotate();
if (initialized &&
(lynx_rot != old_lynx_rot))
lynx_rotation_pending = ROTATION_PENDING_CORE;
}
#if defined(FRONTEND_SUPPORTS_XRGB8888)
......@@ -395,6 +479,25 @@ static void check_variables(void)
/* Reinitialise frameskipping, if required */
if ((frameskip_type != old_frameskip_type) && initialized)
init_frameskip();
old_retro_refresh_rate = retro_refresh_rate;
retro_refresh_rate = 75;
var.key = "handy_refresh_rate";
var.value = NULL;
if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
{
retro_refresh_rate = strtol(var.value, NULL, 10);
retro_refresh_rate = (retro_refresh_rate < 50) ? 50 : retro_refresh_rate;
retro_refresh_rate = (retro_refresh_rate > 120) ? 50 : retro_refresh_rate;
}
retro_cycles_per_frame = (HANDY_SYSTEM_FREQ / retro_refresh_rate);
/* Notify frontend if timing has changed */
if (initialized &&
(retro_refresh_rate != old_retro_refresh_rate))
retro_refresh_rate_updated = true;
}
void retro_init(void)
......@@ -432,8 +535,6 @@ void retro_reset(void)
void retro_deinit(void)
{
initialized = false;
if(lynx)
{
lynx->SaveEEPROM();
......@@ -441,7 +542,24 @@ void retro_deinit(void)
lynx=0;
}
if (framebuffer)
#if defined(_3DS)
linearFree(framebuffer);
#else
free(framebuffer);
#endif
framebuffer = NULL;
libretro_supports_input_bitmasks = false;
lynx_rotation_pending = ROTATION_PENDING_NONE;
lynx_rotation_button_down = false;
lynx_rot = MIKIE_NO_ROTATE;
lynx_width = RETRO_LYNX_WIDTH;
lynx_height = RETRO_LYNX_HEIGHT;
lynx_width_next = RETRO_LYNX_WIDTH;
lynx_height_next = RETRO_LYNX_HEIGHT;
initialized = false;
video_out_enabled = false;
}
void retro_set_environment(retro_environment_t cb)
......@@ -511,18 +629,21 @@ void retro_get_system_info(struct retro_system_info *info)
void retro_get_system_av_info(struct retro_system_av_info *info)
{
struct retro_game_geometry geom = { lynx_width, lynx_height, RETRO_LYNX_WIDTH, RETRO_LYNX_WIDTH, (float) lynx_width / (float) lynx_height };
struct retro_system_timing timing = { RETRO_LYNX_FPS, (float) HANDY_AUDIO_SAMPLE_FREQ };
memset(info, 0, sizeof(*info));
info->geometry = geom;
info->timing = timing;
info->timing.fps = (double)retro_refresh_rate;
info->timing.sample_rate = (double)HANDY_AUDIO_SAMPLE_FREQ;
info->geometry.base_width = lynx_width;
info->geometry.base_height = lynx_height;
info->geometry.max_width = RETRO_LYNX_WIDTH;
info->geometry.max_height = RETRO_LYNX_WIDTH;
info->geometry.aspect_ratio = (float)lynx_width / (float)lynx_height;
}
void retro_run(void)
{
unsigned i, res = 0;
static bool select_pressed_last_frame = false;
bool updated = false;
if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE, &updated) && updated)
check_variables();
......@@ -546,18 +667,23 @@ void retro_run(void)
}
lynx->SetButtonData(res);
if (select_button && !select_pressed_last_frame)
if (select_button && !lynx_rotation_button_down)
{
lynx_rot++;
lynx_rotate();
lynx_rotation_pending = ROTATION_PENDING_CORE;
}
select_pressed_last_frame = select_button;
gAudioLastUpdateCycle = gSystemCycleCount;
/* Check whether current frame should be skipped */
gSkipFrame = 0;
if ((frameskip_type > 0) && retro_audio_buff_active)
lynx_rotation_button_down = select_button;
/* Check whether current frame should be skipped
* > Note: if gSkipFrame is already set, then it
* means a frameskip was requested on the last
* call of retro_run() but no end of frame
* event occurred. We must therefore keep
* gSkipFrame latched on, since any partial frame
* from the previous retro_run() will be incomplete */
if ((frameskip_type > 0) &&
!gSkipFrame &&
retro_audio_buff_active)
{
switch (frameskip_type)
{
......@@ -572,11 +698,8 @@ void retro_run(void)
break;
}
/* Note: We cannot skip this frame if the display
* dimensions have changed (due to screen rotation) */
if (!gSkipFrame ||
(frameskip_counter >= FRAMESKIP_MAX) ||
lynx_rot_updated)
(frameskip_counter >= FRAMESKIP_MAX))
{
gSkipFrame = 0;
frameskip_counter = 0;
......@@ -594,11 +717,29 @@ void retro_run(void)
update_audio_latency = false;
}
while (!newFrame)
if (retro_refresh_rate_updated)
{
update_timing();
retro_refresh_rate_updated = false;
}
gLastRunCycleCount = gSystemCycleCount;
frame_available = false;
while (gSystemCycleCount - gLastRunCycleCount < retro_cycles_per_frame)
lynx->Update();
newFrame = false;
lynx_rot_updated = false;
/* If no end of frame event was produced on this
* run, upload NULL */
if (!frame_available)
video_cb(NULL, lynx_width, lynx_height,
RETRO_LYNX_WIDTH * RETRO_PIX_BYTES);
lynx->FetchAudioSamples();
/* Divide gAudioBufferPointer by number of channels */
audio_batch_cb(soundBuffer, gAudioBufferPointer >> 1);
gAudioBufferPointer = 0;
}
size_t retro_serialize_size(void)
......@@ -665,6 +806,17 @@ bool retro_load_game(const struct retro_game_info *info)
bios_file[0] = '\0';
eeprom_file[0] = '\0';
/* Allocate video buffer */
#if defined(_3DS)
framebuffer = (uint8_t*)linearMemAlign(
RETRO_LYNX_WIDTH * RETRO_LYNX_WIDTH * 4 * sizeof(uint8_t), 128);
#else
framebuffer = (uint8_t*)calloc(1,
RETRO_LYNX_WIDTH * RETRO_LYNX_WIDTH * 4 * sizeof(uint8_t));
#endif
if (!framebuffer)
return false;
environ_cb(RETRO_ENVIRONMENT_SET_INPUT_DESCRIPTORS, desc);
/* Get save directory */
......@@ -744,9 +896,17 @@ bool retro_load_game(const struct retro_game_info *info)
gAudioEnabled = true;
soundBuffer = (int16_t *)&gAudioBuffer;
btn_map = btn_map_no_rot;
/* Apply initial rotation
* > Effect is immediate, so update actual
* lynx_width/lynx_height values here */
lynx_rotate();
lynx_width = lynx_width_next;
lynx_height = lynx_height_next;
initialized = true;
gSkipFrame = 0;
initialized = true;
video_out_enabled = true;
return true;
}
......
libretro/libretro_core_options.h
View file @ 8133b0a0
......@@ -55,6 +55,23 @@ struct retro_core_option_v2_category option_cats_us[] = {
};
struct retro_core_option_v2_definition option_defs_us[] = {
{
"handy_refresh_rate",
"Video Refresh Rate",
NULL,
"Set video update frequency. Internally, the Lynx renders at a variable rate from 0 to 75Hz. Frames that occur between video update events will be dropped. Higher rates may increase video smoothness (depending on actual game frame rate) but can cause tearing on 60Hz displays.",
NULL,
NULL,
{
{ "50", "50Hz" },
{ "60", "60Hz" },
{ "75", "75Hz" },
{ "100", "100Hz" },
{ "120", "120Hz" },
{ NULL, NULL },
},
"60"
},
{
"handy_rot",
"Display Rotation",
......
lynx/mikie.cpp
View file @ 8133b0a0
......@@ -1302,10 +1302,14 @@ ULONG CMikie::DisplayEndOfFrame(void)
break;
}
return 0;
}
void CMikie::AudioEndOfFrame(void)
{
mikbuf.end_frame((gSystemCycleCount - gAudioLastUpdateCycle) / 4);
gAudioBufferPointer = mikbuf.read_samples((blip_sample_t*) gAudioBuffer, HANDY_AUDIO_BUFFER_SIZE / 2);
return 0;
gAudioLastUpdateCycle = gSystemCycleCount;
}
// Peek/Poke memory handlers
......@@ -2422,6 +2426,7 @@ inline void CMikie::Update(void)
if(gSystemCycleCount>0xf0000000) {
gSystemCycleCount-=0x80000000;
gLastRunCycleCount-=0x80000000;
gThrottleNextCycleCheckpoint-=0x80000000;
gAudioLastUpdateCycle-=0x80000000;
mTIM_0_LAST_COUNT-=0x80000000;
......
lynx/mikie.h
View file @ 8133b0a0
......@@ -198,6 +198,7 @@ class CMikie : public CLynxBase
ULONG DisplayRenderLine(void);
ULONG DisplayEndOfFrame(void);
void AudioEndOfFrame(void);
inline void SetCPUSleep(void) {gSystemCPUSleep=TRUE;};
inline void ClearCPUSleep(void) {gSystemCPUSleep=FALSE;gSystemCPUSleep_Saved=FALSE;};
......
lynx/system.cpp
View file @ 8133b0a0
......@@ -353,6 +353,7 @@ void CSystem::HLE_BIOS_FF80(void)
void CSystem::Reset(void)
{
gSystemCycleCount=0;
gLastRunCycleCount=0;
gNextTimerEvent=0;
gCPUBootAddress=0;
gBreakpointHit=FALSE;
......
lynx/system.h
View file @ 8133b0a0
......@@ -75,6 +75,7 @@
#ifdef SYSTEM_CPP
ULONG gSystemCycleCount=0;
ULONG gLastRunCycleCount=0;
ULONG gNextTimerEvent=0;
ULONG gCPUWakeupTime=0;
ULONG gIRQEntryCycle=0;
......@@ -104,6 +105,7 @@ CErrorInterface *gError=NULL;
#else
extern ULONG gSystemCycleCount;
extern ULONG gLastRunCycleCount;
extern ULONG gNextTimerEvent;
extern ULONG gCPUWakeupTime;
extern ULONG gIRQEntryCycle;
......@@ -211,6 +213,11 @@ class CSystem : public CSystemBase
gSystemCycleCount=gNextTimerEvent;
}
inline void FetchAudioSamples(void)
{
mMikie->AudioEndOfFrame();
}
//
// We MUST have separate CPU & RAM peek & poke handlers as all CPU accesses must
// go thru the address generator at $FFF9
......
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