riscos: Fix off-by-one issues with mouse coordinates

libsdl-org · Sep 21, 2020 · c412dc9 · c412dc9
1 parent f59677f
commit c412dc9
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Showing 4 changed files with 22 additions and 18 deletions.
diff --git a/src/video/riscos/SDL_riscosFullScreenVideo.c b/src/video/riscos/SDL_riscosFullScreenVideo.c
@@ -712,12 +712,14 @@ const RISCOS_SDL_PixelFormat *FULLSCREEN_SetMode(int width, int height, int bpp)
 void FULLSCREEN_SetupBanks(_THIS)
 {
    _kernel_swi_regs regs;
-   int block[5];
+   int block[7];
    block[0] = 148; /* Write screen start */
    block[1] = 149; /* Display screen start */
-   block[2] = 4;  /* X eig factor */
-   block[3] = 5;  /* Y eig factor */
-   block[4] = -1;  /* End of list of variables to request */
+   block[2] = 4;   /* X eig factor */
+   block[3] = 5;   /* Y eig factor */
+   block[4] = 11;  /* Screen Width - 1 */
+   block[5] = 12;  /* Screen Height - 1 */
+   block[6] = -1;  /* End of list of variables to request */
 
    regs.r[0] = (int)block;
    regs.r[1] = (int)block;
@@ -727,6 +729,8 @@ void FULLSCREEN_SetupBanks(_THIS)
    this->hidden->bank[1] = (void *)block[1];
    this->hidden->xeig = block[2];
    this->hidden->yeig = block[3];
+   this->hidden->screen_width = block[4];
+   this->hidden->screen_height = block[5];
 }
 
 /* Toggle to full screen mode from the WIMP */

diff --git a/src/video/riscos/SDL_riscosevents.c b/src/video/riscos/SDL_riscosevents.c
@@ -293,7 +293,7 @@ void RISCOS_PollMouseHelper(_THIS, int fullscreen)
           if (fullscreen)
           {
              topLeftX = 0;
-             topLeftY = (this->hidden->height << this->hidden->yeig) - 1;
+             topLeftY = this->hidden->screen_height << this->hidden->yeig;
           } else
           {
              int window_state[9];
@@ -304,7 +304,7 @@ void RISCOS_PollMouseHelper(_THIS, int fullscreen)
 		     _kernel_swi(Wimp_GetWindowState, &regs, &regs);
 
              topLeftX = window_state[1];
-             topLeftY = window_state[4];
+             topLeftY = window_state[4] - 2;
           }
 
           /* Convert co-ordinates to workspace */

diff --git a/src/video/riscos/SDL_riscosmouse.c b/src/video/riscos/SDL_riscosmouse.c
@@ -188,10 +188,10 @@ void FULLSCREEN_WarpWMCursor(_THIS, Uint16 x, Uint16 y)
 	int os_x, os_y;
 	int topLeftY;
 
-	topLeftY = (this->hidden->height << this->hidden->yeig) - 1; /* As per RISCOS_PollMouseHelper */
+	topLeftY = this->hidden->screen_height << this->hidden->yeig; /* As per RISCOS_PollMouseHelper */
 
-	os_x = x << this->hidden->xeig;
-	os_y = topLeftY - (y << this->hidden->yeig);
+	os_x = x << 1;
+	os_y = topLeftY - (y << 1);
 
 	move_block[0] = 3; /* Move cursor */
 	move_block[1] = os_x & 0xFF;
@@ -224,8 +224,8 @@ void WIMP_WarpWMCursor(_THIS, Uint16 x, Uint16 y)
 	_kernel_swi(Wimp_GetWindowState, &regs, &regs);
 
 	/* 90 DPI mapping from SDL pixels to OS units */
-	 osX = (x << 1) + window_state[1];
-	 osY = window_state[4] - (y << 1);
+	osX = (x << 1) + window_state[1];
+	osY = (window_state[4] - 2) - (y << 1);
 
 	block[0] = 3;
 	block[1] = osX & 0xFF;
@@ -258,8 +258,8 @@ SDL_GrabMode RISCOS_GrabInput(_THIS, SDL_GrabMode mode)
       {
          /* Clip to whole screen */
 
-         int r = (this->hidden->screen_width << this->hidden->xeig) - 1;
-         int t = (this->hidden->screen_height << this->hidden->yeig) - 1;
+         int r = this->hidden->screen_width << this->hidden->xeig;
+         int t = this->hidden->screen_height << this->hidden->yeig;
 
 	 block[1] = 0; block[2] = 0; /* Left*/
          block[3] = 0; block[4] = 0; /* Bottom */

diff --git a/src/video/riscos/SDL_wimpvideo.c b/src/video/riscos/SDL_wimpvideo.c
@@ -169,16 +169,16 @@ void WIMP_ReadModeInfo(_THIS)
 	vars[1] = 5;  /* YEig */
 	vars[2] = 9;  /* Log base 2 bpp */
 	vars[3] = 11; /* Screen Width - 1 */
-	vars[4] = 12; /* Screen Depth - 1 */
+	vars[4] = 12; /* Screen Height - 1 */
 	vars[5] = -1; /* Terminate list */
 
 	regs.r[0] = (int)vars;
 	regs.r[1] = (int)vals;
 	_kernel_swi(OS_ReadVduVariables, &regs, &regs);
 	this->hidden->xeig = vals[0];
 	this->hidden->yeig = vals[1];
-	this->hidden->screen_width = vals[3] + 1;
-	this->hidden->screen_height = vals[4] + 1;
+	this->hidden->screen_width = vals[3];
+	this->hidden->screen_height = vals[4];
 }
 
 /* Set device function to call the correct versions for running
@@ -214,8 +214,8 @@ unsigned int WIMP_SetupWindow(_THIS, SDL_Surface *surface)
 	_kernel_oserror *error;
 	int window_data[23];
     int	*window_block = window_data+1;
-	int x = ((this->hidden->screen_width << this->hidden->xeig) - (surface->w << 1)) / 2;
-	int y = ((this->hidden->screen_height << this->hidden->yeig) - (surface->h << 1)) / 2;    
+	int x = (((this->hidden->screen_width + 1) << this->hidden->xeig) - (surface->w << 1)) / 2;
+	int y = (((this->hidden->screen_height + 1) << this->hidden->yeig) - (surface->h << 1)) / 2;
 
 	/* Always delete the window and recreate on a change */
 	if (this->hidden->window_handle) WIMP_DeleteWindow(this);