From 90326ea1f9c9b4396b9b5e82f78112c4e8e9ce6d Mon Sep 17 00:00:00 2001
From: rofl0r <rofl0r@users.noreply.github.com>
Date: Mon, 25 Oct 2021 03:21:34 +0000
Subject: [PATCH] cli: add scaling

the new command line parameter --scale allows to scale the window by
a floating point factor. SDL2 stretches it in hardware to the desired
size, which makes the scaled window run at almost identical speed to
1x scale.
---
 desmume/src/commandline.cpp                   |  5 +++++
 desmume/src/commandline.h                     |  1 +
 desmume/src/frontend/posix/cli/main.cpp       | 21 ++++++++++---------
 .../src/frontend/posix/shared/ctrlssdl.cpp    |  2 +-
 4 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/desmume/src/commandline.cpp b/desmume/src/commandline.cpp
index 2404c45c7..5d6f488b2 100644
--- a/desmume/src/commandline.cpp
+++ b/desmume/src/commandline.cpp
@@ -81,6 +81,7 @@ CommandLine::CommandLine()
 , disable_limiter(0)
 , windowed_fullscreen(0)
 , frameskip(0)
+, scale(1.0)
 , _rtc_day(-1)
 , _rtc_hour(-1)
 {
@@ -123,6 +124,7 @@ static const char* help_string = \
 " --windowed-fullscreen" ENDL
 "                            Launches in windowed fullscreen (same as alt+enter)" ENDL
 #else
+" --scale N                  scale factor for window; default 1.0" ENDL
 " --nojoy                    Disables joystick support" ENDL
 #endif
 " --disable-sound            Disables the sound output" ENDL
@@ -198,6 +200,7 @@ ENDL
 #define OPT_3D_TEXTURE_UPSCALE 81
 #define OPT_GPU_RESOLUTION_MULTIPLIER 82
 #define OPT_FRAMESKIP 83
+#define OPT_SCALE 84
 #define OPT_JIT_SIZE 100
 
 #define OPT_CONSOLE_TYPE 200
@@ -261,6 +264,7 @@ bool CommandLine::parse(int argc,char **argv)
 				{ "windowed-fullscreen", no_argument, &windowed_fullscreen, 1 },
 			#else
 				{ "nojoy", no_argument, &_commandline_linux_nojoy, 1},
+				{ "scale", required_argument, NULL, OPT_SCALE},
 			#endif
 			{ "frameskip", required_argument, NULL, OPT_FRAMESKIP},
 			{ "disable-sound", no_argument, &disable_sound, 1},
@@ -339,6 +343,7 @@ bool CommandLine::parse(int argc,char **argv)
 		case OPT_3D_RENDER: _render3d = optarg; break;
 		case OPT_3D_TEXTURE_UPSCALE: texture_upscale = atoi(optarg); break;
 		case OPT_GPU_RESOLUTION_MULTIPLIER: gpu_resolution_multiplier = atoi(optarg); break;
+		case OPT_SCALE: scale = atof(optarg); break;
 		case OPT_FRAMESKIP: frameskip = atoi(optarg); break;
 
 		//RTC settings
diff --git a/desmume/src/commandline.h b/desmume/src/commandline.h
index 4f87f8a6e..e75bd795c 100644
--- a/desmume/src/commandline.h
+++ b/desmume/src/commandline.h
@@ -49,6 +49,7 @@ public:
 	int texture_upscale;
 	int gpu_resolution_multiplier;
 	int language;
+	float scale;
 	std::string nds_file;
 	std::string play_movie_file;
 	std::string record_movie_file;
diff --git a/desmume/src/frontend/posix/cli/main.cpp b/desmume/src/frontend/posix/cli/main.cpp
index 0d3d03530..f012cef5a 100644
--- a/desmume/src/frontend/posix/cli/main.cpp
+++ b/desmume/src/frontend/posix/cli/main.cpp
@@ -262,17 +262,17 @@ static void
 resizeWindow_stub (u16 width, u16 height, void *screen_texture) {
 }
 
-static void
-Draw( void) {
+static void Draw(class configured_features *cfg) {
+	const float scale = cfg->scale;
+	const unsigned w = GPU_FRAMEBUFFER_NATIVE_WIDTH, h = GPU_FRAMEBUFFER_NATIVE_HEIGHT;
+	const int ws = w * scale, hs = h * scale;
 	const NDSDisplayInfo &displayInfo = GPU->GetDisplayInfo();
-	const size_t pixCount = GPU_FRAMEBUFFER_NATIVE_WIDTH * GPU_FRAMEBUFFER_NATIVE_HEIGHT;
+	const size_t pixCount = w * h;
 	ColorspaceApplyIntensityToBuffer16<false, false>(displayInfo.nativeBuffer16[NDSDisplayID_Main],  pixCount, displayInfo.backlightIntensity[NDSDisplayID_Main]);
 	ColorspaceApplyIntensityToBuffer16<false, false>(displayInfo.nativeBuffer16[NDSDisplayID_Touch], pixCount, displayInfo.backlightIntensity[NDSDisplayID_Touch]);
-	static const SDL_Rect destrect[2] = {
-		{ 0,0,
-		  GPU_FRAMEBUFFER_NATIVE_WIDTH, GPU_FRAMEBUFFER_NATIVE_HEIGHT},
-		{ 0, GPU_FRAMEBUFFER_NATIVE_HEIGHT,
-		  GPU_FRAMEBUFFER_NATIVE_WIDTH, GPU_FRAMEBUFFER_NATIVE_HEIGHT},
+	SDL_Rect destrect[2] = {
+		{ 0, 0 , ws, hs},
+		{ 0, hs, ws, hs},
 	};
 	unsigned i, off = 0, n = pixCount*2;
 	for(i = 0; i < 2; ++i) {
@@ -481,9 +481,10 @@ int main(int argc, char ** argv) {
       return 1;
     }
 
+    nds_screen_size_ratio = my_config.scale;
     sdl_videoFlags |= SDL_WINDOW_OPENGL;
     window = SDL_CreateWindow( "Desmume SDL", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
-	256, 384, sdl_videoFlags );
+	256*my_config.scale, 384*my_config.scale, sdl_videoFlags );
 
     if ( !window ) {
       fprintf( stderr, "Window creation failed: %s\n", SDL_GetError( ) );
@@ -541,7 +542,7 @@ int main(int argc, char ** argv) {
     DrawHUD();
 #endif
 
-    Draw();
+    Draw(&my_config);
 
 #ifdef HAVE_LIBAGG
     osd->clear();
diff --git a/desmume/src/frontend/posix/shared/ctrlssdl.cpp b/desmume/src/frontend/posix/shared/ctrlssdl.cpp
index febf08e27..bc073b43b 100644
--- a/desmume/src/frontend/posix/shared/ctrlssdl.cpp
+++ b/desmume/src/frontend/posix/shared/ctrlssdl.cpp
@@ -259,7 +259,7 @@ u16 get_set_joy_key(int index) {
 
 static signed long
 screen_to_touch_range( signed long scr, float size_ratio) {
-  return (signed long)((float)scr * size_ratio);
+  return (signed long)((float)scr / size_ratio);
 }
 
 /* Set mouse coordinates */