From e9f7a1b359f3b5844053827272c26214d2836f01 Mon Sep 17 00:00:00 2001
From: expikr <[EMAIL REDACTED]>
Date: Wed, 6 Nov 2024 19:08:09 +0800
Subject: [PATCH] fix relative system scale function on Windows
source: https://web.archive.org/web/20161202223814/https://ihme.org/~orbik/random_stuff/donewmouseaccel.png
Co-Authored-By: Sam Lantinga <slouken@libsdl.org>
---
src/events/SDL_mouse.c | 127 ++------------
src/events/SDL_mouse_c.h | 9 +-
src/video/windows/SDL_windowsmouse.c | 238 +++++++++++++++++----------
3 files changed, 174 insertions(+), 200 deletions(-)
diff --git a/src/events/SDL_mouse.c b/src/events/SDL_mouse.c
index a62c1f9d1f92f..2923e8b52b415 100644
--- a/src/events/SDL_mouse.c
+++ b/src/events/SDL_mouse.c
@@ -588,111 +588,6 @@ void SDL_SendMouseMotion(Uint64 timestamp, SDL_Window *window, SDL_MouseID mouse
SDL_PrivateSendMouseMotion(timestamp, window, mouseID, relative, x, y);
}
-static float CalculateSystemScale(SDL_Mouse *mouse, SDL_Window *window, const float *x, const float *y)
-{
- int i;
- int n = mouse->num_system_scale_values;
- float *v = mouse->system_scale_values;
- float speed, coef, scale;
-
- // If we're using a single scale value, return that
- if (n == 1) {
- scale = v[0];
- } else {
- speed = SDL_sqrtf((*x * *x) + (*y * *y));
- for (i = 0; i < (n - 2); i += 2) {
- if (speed < v[i + 2]) {
- break;
- }
- }
- if (i == (n - 2)) {
- scale = v[n - 1];
- } else if (speed <= v[i]) {
- scale = v[i + 1];
- } else {
- coef = (speed - v[i]) / (v[i + 2] - v[i]);
- scale = v[i + 1] + (coef * (v[i + 3] - v[i + 1]));
- }
- }
-#ifdef SDL_PLATFORM_WIN32
- {
- // On Windows the mouse speed is affected by the content scale
- SDL_VideoDisplay *display;
-
- if (window) {
- display = SDL_GetVideoDisplayForWindow(window);
- } else {
- display = SDL_GetVideoDisplay(SDL_GetPrimaryDisplay());
- }
- if (display) {
- scale *= display->content_scale;
- }
- }
-#endif
- return scale;
-}
-
-// You can set either a single scale, or a set of {speed, scale} values in ascending order
-bool SDL_SetMouseSystemScale(int num_values, const float *values)
-{
- SDL_Mouse *mouse = SDL_GetMouse();
- float *v;
-
- if (num_values == mouse->num_system_scale_values &&
- SDL_memcmp(values, mouse->system_scale_values, num_values * sizeof(*values)) == 0) {
- // Nothing has changed
- return true;
- }
-
- if (num_values < 1) {
- return SDL_SetError("You must have at least one scale value");
- }
-
- if (num_values > 1) {
- // Validate the values
- int i;
-
- if (num_values < 4 || (num_values % 2) != 0) {
- return SDL_SetError("You must pass a set of {speed, scale} values");
- }
-
- for (i = 0; i < (num_values - 2); i += 2) {
- if (values[i] >= values[i + 2]) {
- return SDL_SetError("Speed values must be in ascending order");
- }
- }
- }
-
- v = (float *)SDL_realloc(mouse->system_scale_values, num_values * sizeof(*values));
- if (!v) {
- return false;
- }
- SDL_memcpy(v, values, num_values * sizeof(*values));
-
- mouse->num_system_scale_values = num_values;
- mouse->system_scale_values = v;
- return true;
-}
-
-static void GetScaledMouseDeltas(SDL_Mouse *mouse, SDL_Window *window, float *x, float *y)
-{
- if (mouse->relative_mode) {
- if (mouse->enable_relative_speed_scale) {
- *x *= mouse->relative_speed_scale;
- *y *= mouse->relative_speed_scale;
- } else if (mouse->enable_relative_system_scale && mouse->num_system_scale_values > 0) {
- float relative_system_scale = CalculateSystemScale(mouse, window, x, y);
- *x *= relative_system_scale;
- *y *= relative_system_scale;
- }
- } else {
- if (mouse->enable_normal_speed_scale) {
- *x *= mouse->normal_speed_scale;
- *y *= mouse->normal_speed_scale;
- }
- }
-}
-
static void ConstrainMousePosition(SDL_Mouse *mouse, SDL_Window *window, float *x, float *y)
{
/* make sure that the pointers find themselves inside the windows,
@@ -787,7 +682,21 @@ static void SDL_PrivateSendMouseMotion(Uint64 timestamp, SDL_Window *window, SDL
}
if (relative) {
- GetScaledMouseDeltas(mouse, window, &x, &y);
+ if (mouse->relative_mode) {
+ if (mouse->enable_relative_speed_scale) {
+ x *= mouse->relative_speed_scale;
+ y *= mouse->relative_speed_scale;
+ } else if (mouse->enable_relative_system_scale) {
+ if (mouse->ApplySystemScale) {
+ mouse->ApplySystemScale(mouse->system_scale_data, timestamp, window, mouseID, &x, &y);
+ }
+ }
+ } else {
+ if (mouse->enable_normal_speed_scale) {
+ x *= mouse->normal_speed_scale;
+ y *= mouse->normal_speed_scale;
+ }
+ }
xrel = x;
yrel = y;
x = (mouse->last_x + xrel);
@@ -1118,12 +1027,6 @@ void SDL_QuitMouse(void)
}
mouse->num_clickstates = 0;
- if (mouse->system_scale_values) {
- SDL_free(mouse->system_scale_values);
- mouse->system_scale_values = NULL;
- }
- mouse->num_system_scale_values = 0;
-
SDL_RemoveHintCallback(SDL_HINT_MOUSE_DOUBLE_CLICK_TIME,
SDL_MouseDoubleClickTimeChanged, mouse);
diff --git a/src/events/SDL_mouse_c.h b/src/events/SDL_mouse_c.h
index 9c324b4e74490..6b646a72b8fc4 100644
--- a/src/events/SDL_mouse_c.h
+++ b/src/events/SDL_mouse_c.h
@@ -82,6 +82,10 @@ typedef struct
// Get absolute mouse coordinates. (x) and (y) are never NULL and set to zero before call.
SDL_MouseButtonFlags (*GetGlobalMouseState)(float *x, float *y);
+ // Platform-specific system mouse transform
+ void (*ApplySystemScale)(void *internal, Uint64 timestamp, SDL_Window *window, SDL_MouseID mouseID, float *x, float *y);
+ void *system_scale_data;
+
// Data common to all mice
SDL_Window *focus;
float x;
@@ -104,8 +108,6 @@ typedef struct
bool enable_relative_speed_scale;
float relative_speed_scale;
bool enable_relative_system_scale;
- int num_system_scale_values;
- float *system_scale_values;
Uint32 double_click_time;
int double_click_radius;
bool touch_mouse_events;
@@ -162,9 +164,6 @@ extern void SDL_SetMouseFocus(SDL_Window *window);
// Update the mouse capture window
extern bool SDL_UpdateMouseCapture(bool force_release);
-// You can set either a single scale, or a set of {speed, scale} values in sorted order
-extern bool SDL_SetMouseSystemScale(int num_values, const float *values);
-
// Send a mouse motion event
extern void SDL_SendMouseMotion(Uint64 timestamp, SDL_Window *window, SDL_MouseID mouseID, bool relative, float x, float y);
diff --git a/src/video/windows/SDL_windowsmouse.c b/src/video/windows/SDL_windowsmouse.c
index a6b80729500ea..3e09b92be54b3 100644
--- a/src/video/windows/SDL_windowsmouse.c
+++ b/src/video/windows/SDL_windowsmouse.c
@@ -29,6 +29,7 @@
#include "../SDL_video_c.h"
#include "../../events/SDL_mouse_c.h"
#include "../../joystick/usb_ids.h"
+#include "../../core/windows/SDL_windows.h" // for checking windows version
typedef struct CachedCursor
@@ -47,9 +48,22 @@ struct SDL_CursorData
HCURSOR cursor;
};
+typedef struct
+{
+ Uint64 xs[5];
+ Uint64 ys[5];
+ Sint64 residual[2];
+ Uint32 dpiscale;
+ Uint32 dpidenom;
+ int last_node;
+ bool enhanced;
+ bool dpiaware;
+} WIN_MouseData;
+
DWORD SDL_last_warp_time = 0;
HCURSOR SDL_cursor = NULL;
static SDL_Cursor *SDL_blank_cursor = NULL;
+static WIN_MouseData WIN_system_scale_data;
static SDL_Cursor *WIN_CreateCursorAndData(HCURSOR hcursor)
{
@@ -521,6 +535,95 @@ static SDL_MouseButtonFlags WIN_GetGlobalMouseState(float *x, float *y)
return result;
}
+static void WIN_ApplySystemScale(void *internal, Uint64 timestamp, SDL_Window *window, SDL_MouseID mouseID, float *x, float *y)
+{
+ if (!internal) {
+ return;
+ }
+ WIN_MouseData *data = (WIN_MouseData *)internal;
+
+ SDL_VideoDisplay *display = window ? SDL_GetVideoDisplayForWindow(window) : SDL_GetVideoDisplay(SDL_GetPrimaryDisplay());
+
+ Sint64 ix = (Sint64)*x * 65536;
+ Sint64 iy = (Sint64)*y * 65536;
+ Uint32 dpi = display ? (Uint32)(display->content_scale * USER_DEFAULT_SCREEN_DPI) : USER_DEFAULT_SCREEN_DPI;
+
+ if (!data->enhanced) { // early return if flat scale
+ dpi = data->dpiscale * (data->dpiaware ? dpi : USER_DEFAULT_SCREEN_DPI);
+ ix *= dpi;
+ iy *= dpi;
+ ix /= USER_DEFAULT_SCREEN_DPI;
+ iy /= USER_DEFAULT_SCREEN_DPI;
+ ix /= 32;
+ iy /= 32;
+ // data->residual[0] += ix;
+ // data->residual[1] += iy;
+ // ix = 65536 * (data->residual[0] / 65536);
+ // iy = 65536 * (data->residual[1] / 65536);
+ // data->residual[0] -= ix;
+ // data->residual[1] -= iy;
+ *x = (float)ix / 65536.0f;
+ *y = (float)iy / 65536.0f;
+ return;
+ }
+
+ Uint64 *xs = data->xs;
+ Uint64 *ys = data->ys;
+ Uint64 absx = SDL_abs(ix);
+ Uint64 absy = SDL_abs(iy);
+ Uint64 speed = SDL_min(absx, absy) + (SDL_max(absx, absy) << 1); // super cursed approximation used by Windows
+ if (speed == 0) {
+ return;
+ }
+
+ int i, j, k;
+ for (i = 1; i < 5; i++) {
+ j = i;
+ if (speed < xs[j]) {
+ break;
+ }
+ }
+ i -= 1;
+ j -= 1;
+ k = data->last_node;
+ data->last_node = j;
+
+ Uint32 denom = data->dpidenom;
+ Sint64 scale = 0;
+ Sint64 xdiff = xs[j+1] - xs[j];
+ Sint64 ydiff = ys[j+1] - ys[j];
+ if (xdiff != 0) {
+ Sint64 slope = ydiff / xdiff;
+ Sint64 inter = slope * xs[i] - ys[i];
+ scale += slope - inter / speed;
+ }
+
+ if (j > k) {
+ denom <<= 1;
+ xdiff = xs[k+1] - xs[k];
+ ydiff = ys[k+1] - ys[k];
+ if (xdiff != 0) {
+ Sint64 slope = ydiff / xdiff;
+ Sint64 inter = slope * xs[k] - ys[k];
+ scale += slope - inter / speed;
+ }
+ }
+
+ scale *= dpi;
+ ix *= scale;
+ iy *= scale;
+ ix /= denom;
+ iy /= denom;
+ // data->residual[0] += ix;
+ // data->residual[1] += iy;
+ // ix = 65536 * (data->residual[0] / 65536);
+ // iy = 65536 * (data->residual[1] / 65536);
+ // data->residual[0] -= ix;
+ // data->residual[1] -= iy;
+ *x = (float)ix / 65536.0f;
+ *y = (float)iy / 65536.0f;
+}
+
void WIN_InitMouse(SDL_VideoDevice *_this)
{
SDL_Mouse *mouse = SDL_GetMouse();
@@ -534,6 +637,8 @@ void WIN_InitMouse(SDL_VideoDevice *_this)
mouse->SetRelativeMouseMode = WIN_SetRelativeMouseMode;
mouse->CaptureMouse = WIN_CaptureMouse;
mouse->GetGlobalMouseState = WIN_GetGlobalMouseState;
+ mouse->ApplySystemScale = WIN_ApplySystemScale;
+ mouse->system_scale_data = &WIN_system_scale_data;
SDL_SetDefaultCursor(WIN_CreateDefaultCursor());
@@ -550,101 +655,68 @@ void WIN_QuitMouse(SDL_VideoDevice *_this)
}
}
-/* For a great description of how the enhanced mouse curve works, see:
- * https://superuser.com/questions/278362/windows-mouse-acceleration-curve-smoothmousexcurve-and-smoothmouseycurve
- * http://www.esreality.com/?a=post&id=1846538/
- */
-static bool LoadFiveFixedPointFloats(const BYTE *bytes, float *values)
+static void ReadMouseCurve(int v, Uint64 xs[5], Uint64 ys[5])
{
+ bool win8 = WIN_IsWindows8OrGreater();
+ DWORD xbuff[10] = {
+ 0x00000000, 0,
+ 0x00006e15, 0,
+ 0x00014000, 0,
+ 0x0003dc29, 0,
+ 0x00280000, 0
+ };
+ DWORD ybuff[10] = {
+ 0x00000000, 0,
+ win8 ? 0x000111fd : 0x00015eb8, 0,
+ win8 ? 0x00042400 : 0x00054ccd, 0,
+ win8 ? 0x0012fc00 : 0x00184ccd, 0,
+ win8 ? 0x01bbc000 : 0x02380000, 0
+ };
+ DWORD xsize = sizeof(xbuff);
+ DWORD ysize = sizeof(ybuff);
+ HKEY open_handle;
+ if (RegOpenKeyExW(HKEY_CURRENT_USER, L"Control Panel\\Mouse", 0, KEY_READ, &open_handle) == ERROR_SUCCESS) {
+ RegQueryValueExW(open_handle, L"SmoothMouseXCurve", NULL, NULL, (BYTE*)xbuff, &xsize);
+ RegQueryValueExW(open_handle, L"SmoothMouseYCurve", NULL, NULL, (BYTE*)ybuff, &ysize);
+ RegCloseKey(open_handle);
+ }
+ xs[0] = 0; // first node must always be origin
+ ys[0] = 0; // first node must always be origin
int i;
-
- for (i = 0; i < 5; ++i) {
- float fraction = (float)((Uint16)bytes[1] << 8 | bytes[0]) / 65535.0f;
- float value = (float)(((Uint16)bytes[3] << 8) | bytes[2]) + fraction;
- *values++ = value;
- bytes += 8;
+ for (i = 1; i < 5; i++) {
+ xs[i] = (7 * (Uint64)xbuff[i*2]);
+ ys[i] = (v * (Uint64)ybuff[i*2]) << 17;
}
- return true;
}
-static void WIN_SetEnhancedMouseScale(int mouse_speed)
+void WIN_UpdateMouseSystemScale(void)
{
- float scale = (float)mouse_speed / 10.0f;
- HKEY hKey;
- DWORD dwType = REG_BINARY;
- BYTE value[40];
- DWORD length = sizeof(value);
- int i;
- float xpoints[5];
- float ypoints[5];
- float scale_points[10];
- const int dpi = USER_DEFAULT_SCREEN_DPI; // FIXME, how do we handle different monitors with different DPI?
- const float display_factor = 3.5f * (150.0f / dpi);
-
- if (RegOpenKeyExW(HKEY_CURRENT_USER, L"Control Panel\\Mouse", 0, KEY_READ, &hKey) == ERROR_SUCCESS) {
- if (RegQueryValueExW(hKey, L"SmoothMouseXCurve", 0, &dwType, value, &length) == ERROR_SUCCESS &&
- LoadFiveFixedPointFloats(value, xpoints) &&
- RegQueryValueExW(hKey, L"SmoothMouseYCurve", 0, &dwType, value, &length) == ERROR_SUCCESS &&
- LoadFiveFixedPointFloats(value, ypoints)) {
- for (i = 0; i < 5; ++i) {
- float gain;
- if (xpoints[i] > 0.0f) {
- gain = (ypoints[i] / xpoints[i]) * scale;
- } else {
- gain = 0.0f;
- }
- scale_points[i * 2] = xpoints[i];
- scale_points[i * 2 + 1] = gain / display_factor;
- // SDL_Log("Point %d = %f,%f\n", i, scale_points[i * 2], scale_points[i * 2 + 1]);
- }
- SDL_SetMouseSystemScale(SDL_arraysize(scale_points), scale_points);
- }
- RegCloseKey(hKey);
+ SDL_Mouse *mouse = SDL_GetMouse();
+
+ if (mouse->ApplySystemScale == WIN_ApplySystemScale) {
+ mouse->system_scale_data = &WIN_system_scale_data;
}
-}
-static void WIN_SetLinearMouseScale(int mouse_speed)
-{
- static float mouse_speed_scale[] = {
- 0.0f,
- 1 / 32.0f,
- 1 / 16.0f,
- 1 / 8.0f,
- 2 / 8.0f,
- 3 / 8.0f,
- 4 / 8.0f,
- 5 / 8.0f,
- 6 / 8.0f,
- 7 / 8.0f,
- 1.0f,
- 1.25f,
- 1.5f,
- 1.75f,
- 2.0f,
- 2.25f,
- 2.5f,
- 2.75f,
- 3.0f,
- 3.25f,
- 3.5f
- };
+ // always reinitialize to valid defaults, whether fetch was successful or not.
+ WIN_MouseData *data = &WIN_system_scale_data;
+ data->residual[0] = 0;
+ data->residual[1] = 0;
+ data->dpiscale = 32;
+ data->dpidenom = (10 * (WIN_IsWindows8OrGreater() ? 120 : 150)) << 16;
+ data->dpiaware = WIN_IsPerMonitorV2DPIAware(SDL_GetVideoDevice());
+ data->enhanced = false;
- if (mouse_speed > 0 && mouse_speed < SDL_arraysize(mouse_speed_scale)) {
- SDL_SetMouseSystemScale(1, &mouse_speed_scale[mouse_speed]);
+ int v = 10;
+ if (SystemParametersInfo(SPI_GETMOUSESPEED, 0, &v, 0)) {
+ v = SDL_max(1, SDL_min(v, 20));
+ data->dpiscale = SDL_max(SDL_max(v, (v - 2) << 2), (v - 6) << 3);
}
-}
-void WIN_UpdateMouseSystemScale(void)
-{
- int mouse_speed;
- int params[3] = { 0, 0, 0 };
-
- if (SystemParametersInfo(SPI_GETMOUSESPEED, 0, &mouse_speed, 0) &&
- SystemParametersInfo(SPI_GETMOUSE, 0, params, 0)) {
+ int params[3];
+ if (SystemParametersInfo(SPI_GETMOUSE, 0, ¶ms, 0)) {
+ data->enhanced = params[2] ? true : false;
if (params[2]) {
- WIN_SetEnhancedMouseScale(mouse_speed);
- } else {
- WIN_SetLinearMouseScale(mouse_speed);
+ ReadMouseCurve(v, data->xs, data->ys);
}
}
}