From db6225eb5d0e329447f12f6bf8d7b07abfd37518 Mon Sep 17 00:00:00 2001
From: helixhorned <helixhorned@1a8010ca-5511-0410-912e-c29ae57300e0>
Date: Mon, 9 Apr 2012 19:22:00 +0000
Subject: [PATCH] On Windows, auto-determine r_screenaspect on startup.

Consequently, it's not saved as a setting in either the game or editor
config files.  We do this by calling "GetSystemMetrics(SM_CXSCREEN)"
(accordingly for y) and calculating the cvar by dividing common factors,
since it has to be in the form WWHH.  This may fail for _really_ strange
screen dimensions, so a log message is printed at the very beginning.

git-svn-id: https://svn.eduke32.com/eduke32@2601 1a8010ca-5511-0410-912e-c29ae57300e0
---
 polymer/eduke32/build/src/baselayer.c | 11 +++++--
 polymer/eduke32/build/src/config.c    | 11 +++++--
 polymer/eduke32/build/src/winlayer.c  | 41 +++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 5 deletions(-)

diff --git a/polymer/eduke32/build/src/baselayer.c b/polymer/eduke32/build/src/baselayer.c
index 11dc88be6..bab97e02b 100644
--- a/polymer/eduke32/build/src/baselayer.c
+++ b/polymer/eduke32/build/src/baselayer.c
@@ -297,11 +297,18 @@ static int32_t osdcmd_cvar_set_baselayer(const osdfuncparm_t *parm)
 int32_t baselayer_init(void)
 {
     uint32_t i;
-
+#ifdef _WIN32
+// on Windows, don't save the "r_screenaspect" cvar because the physical screen size is
+// determined at startup
+# define SCREENASPECT_CVAR_TYPE (CVAR_UINT|CVAR_NOSAVE)
+#else
+# define SCREENASPECT_CVAR_TYPE (CVAR_UINT)
+#endif
     cvar_t cvars_engine[] =
     {
         { "r_usenewaspect","r_usenewaspect: enable/disable new screen aspect ratio determination code",(void *) &r_usenewaspect, CVAR_BOOL, 0, 1 },
-        { "r_screenaspect","r_screenaspect: if using the new aspect code and in fullscreen, screen aspect ratio in the form XXYY, e.g. 1609 for 16:9",(void *) &r_screenxy, CVAR_UINT, 100, 9999 },
+        { "r_screenaspect","r_screenaspect: if using the new aspect code and in fullscreen, screen aspect ratio in the form XXYY, e.g. 1609 for 16:9",
+          (void *) &r_screenxy, SCREENASPECT_CVAR_TYPE, 100, 9999 },
         { "r_novoxmips","r_novoxmips: turn off/on the use of mipmaps when rendering 8-bit voxels",(void *) &novoxmips, CVAR_BOOL, 0, 1 },
         { "r_voxels","r_voxels: enable/disable automatic sprite->voxel rendering",(void *) &usevoxels, CVAR_BOOL, 0, 1 },
 #ifdef YAX_ENABLE
diff --git a/polymer/eduke32/build/src/config.c b/polymer/eduke32/build/src/config.c
index c231f64ec..5fd62a662 100644
--- a/polymer/eduke32/build/src/config.c
+++ b/polymer/eduke32/build/src/config.c
@@ -201,13 +201,14 @@ int32_t loadsetup(const char *fn)
 #endif
     if (readconfig(fp, "r_usenewaspect", val, VL) > 0)
         r_usenewaspect = !!atoi_safe(val);
+#ifndef RENDERTYPEWIN
     if (readconfig(fp, "r_screenxy", val, VL) > 0)
     {
         r_screenxy = clamp(atoi_safe(val), 0, 9999);
         if (r_screenxy/100==0 || r_screenxy%100==0)
             r_screenxy = 403;
     }
-
+#endif
     if (readconfig(fp, "gameexecutable", val, VL) > 0)
         Bstrcpy(game_executable, val);
 
@@ -399,8 +400,10 @@ int32_t writesetup(const char *fn)
 #endif
              "; Use new aspect determination code? (classic/Polymost)\n"
              "r_usenewaspect = %d\n"
+#ifndef RENDERTYPEWIN
              "; Screen aspect for fullscreen, in the form WWHH (e.g. 1609 for 16:9)\n"
              "r_screenxy = %d\n"
+#endif
              "\n"
 
 #ifdef RENDERTYPEWIN
@@ -569,8 +572,10 @@ int32_t writesetup(const char *fn)
              glusetexcache, glusememcache, gltexfiltermode, glanisotropy,r_downsize,glusetexcompr,
              shadescale,
 #endif
-             r_usenewaspect, r_screenxy,
-#ifdef RENDERTYPEWIN
+             r_usenewaspect,
+#ifndef RENDERTYPEWIN
+             r_screenxy,
+#else
              maxrefreshfreq, windowpos, windowx, windowy,
 #endif
              vid_gamma_3d>=0?vid_gamma_3d:vid_gamma,
diff --git a/polymer/eduke32/build/src/winlayer.c b/polymer/eduke32/build/src/winlayer.c
index c2d6a3199..a1be5ab9f 100644
--- a/polymer/eduke32/build/src/winlayer.c
+++ b/polymer/eduke32/build/src/winlayer.c
@@ -28,6 +28,7 @@
 
 #include "compat.h"
 #include "winlayer.h"
+#include "baselayer.h"
 #include "pragmas.h"
 #include "build.h"
 #include "a.h"
@@ -299,6 +300,31 @@ static void SignalHandler(int32_t signum)
     }
 }
 
+static void divcommon(int32_t *ap, int32_t *bp)
+{
+    const int32_t p[] = {2,3,5,7,11,13,17,19};
+    const int32_t N = (int32_t)(sizeof(p)/sizeof(p[0]));
+    int32_t a=*ap, b=*bp;
+
+    while (1)
+    {
+        int32_t i;
+
+        for (i=0; i<N; i++)
+            if (a%p[i] == 0 && b%p[i]==0)
+            {
+                a /= p[i];
+                b /= p[i];
+                break;
+            }
+        if (i == N)
+            break;
+    }
+
+    *ap = a;
+    *bp = b;
+}
+
 //
 // WinMain() -- main Windows entry point
 //
@@ -497,6 +523,21 @@ int32_t WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, in
     startwin_open();
     baselayer_init();
 
+    // determine physical screen size
+    {
+        const int32_t oscreenx = GetSystemMetrics(SM_CXSCREEN);
+        const int32_t oscreeny = GetSystemMetrics(SM_CYSCREEN);
+        int32_t screenx=oscreenx, screeny=oscreeny, good=0;
+
+        divcommon(&screenx, &screeny);
+
+        if (screenx >= 1 && screenx <= 99 && screeny >= 1 && screeny <= 99)
+            r_screenxy = screenx*100 + screeny, good=1;
+
+        initprintf("Automatic fullscreen size determination: %d %d -> %d %d%s.\n",
+                   oscreenx, oscreeny, screenx, screeny, good?"":" (failed)");
+    }
+
     r = app_main(_buildargc, _buildargv);
 
     fclose(stdout);