Feature: allow custom width/height of screenshot via console

Reworked how the screenshot command works while keeping it backwards
compatible. It can now more freely understand arguments, and has
the ability to make SC_DEFAULTZOOM screenshots.

3 files changed, 86 insertions, 37 deletions

diff --git a/src/console_cmds.cpp b/src/console_cmds.cpp
index 905a41c3e..3f454b1aa 100644
--- a/src/console_cmds.cpp
+++ b/src/console_cmds.cpp
@@ -1409,46 +1409,76 @@ DEF_CONSOLE_CMD(ConAlias)
 DEF_CONSOLE_CMD(ConScreenShot)
 {
 	if (argc == 0) {
-		IConsoleHelp("Create a screenshot of the game. Usage: 'screenshot [big | giant | no_con | minimap] [file name]'");
-		IConsoleHelp("'big' makes a zoomed-in screenshot of the visible area, 'giant' makes a screenshot of the "
-				"whole map, 'no_con' hides the console to create the screenshot. 'big' or 'giant' "
-				"screenshots are always drawn without console. "
-				"'minimap' makes a top-viewed minimap screenshot of whole world which represents one tile by one pixel.");
+		IConsoleHelp("Create a screenshot of the game. Usage: 'screenshot [viewport | normal | big | giant | minimap] [no_con] [size <width> <height>] [<filename>]'");
+		IConsoleHelp("'viewport' (default) makes a screenshot of the current viewport (including menus, windows, ..), "
+				"'normal' makes a screenshot of the visible area, "
+				"'big' makes a zoomed-in screenshot of the visible area, "
+				"'giant' makes a screenshot of the whole map, "
+				"'minimap' makes a top-viewed minimap screenshot of the whole world which represents one tile by one pixel. "
+				"'no_con' hides the console to create the screenshot (only useful in combination with 'viewport'). "
+				"'size' sets the width and height of the viewport to make a screenshot of (only useful in combination with 'normal' or 'big').");
 		return true;
 	}
 
-	if (argc > 3) return false;
+	if (argc > 7) return false;
 
 	ScreenshotType type = SC_VIEWPORT;
+	uint32 width = 0;
+	uint32 height = 0;
 	const char *name = nullptr;
-
-	if (argc > 1) {
-		if (strcmp(argv[1], "big") == 0) {
-			/* screenshot big [filename] */
+	uint32 arg_index = 1;
+
+	if (argc > arg_index) {
+		if (strcmp(argv[arg_index], "viewport") == 0) {
+			type = SC_VIEWPORT;
+			arg_index += 1;
+		} else if (strcmp(argv[arg_index], "normal") == 0) {
+			type = SC_DEFAULTZOOM;
+			arg_index += 1;
+		} else if (strcmp(argv[arg_index], "big") == 0) {
 			type = SC_ZOOMEDIN;
-			if (argc > 2) name = argv[2];
-		} else if (strcmp(argv[1], "giant") == 0) {
-			/* screenshot giant [filename] */
+			arg_index += 1;
+		} else if (strcmp(argv[arg_index], "giant") == 0) {
 			type = SC_WORLD;
-			if (argc > 2) name = argv[2];
-		} else if (strcmp(argv[1], "minimap") == 0) {
-			/* screenshot minimap [filename] */
+			arg_index += 1;
+		} else if (strcmp(argv[arg_index], "minimap") == 0) {
 			type = SC_MINIMAP;
-			if (argc > 2) name = argv[2];
-		} else if (strcmp(argv[1], "no_con") == 0) {
-			/* screenshot no_con [filename] */
-			IConsoleClose();
-			if (argc > 2) name = argv[2];
-		} else if (argc == 2) {
-			/* screenshot filename */
-			name = argv[1];
-		} else {
-			/* screenshot argv[1] argv[2] - invalid */
-			return false;
+			arg_index += 1;
+		}
+	}
+
+	if (argc > arg_index && strcmp(argv[arg_index], "no_con") == 0) {
+		if (type != SC_VIEWPORT) {
+			IConsoleError("'no_con' can only be used in combination with 'viewport'");
+			return true;
+		}
+		IConsoleClose();
+		arg_index += 1;
+	}
+
+	if (argc > arg_index + 2 && strcmp(argv[arg_index], "size") == 0) {
+		/* size <width> <height> */
+		if (type != SC_DEFAULTZOOM && type != SC_ZOOMEDIN) {
+			IConsoleError("'size' can only be used in combination with 'normal' or 'big'");
+			return true;
 		}
+		GetArgumentInteger(&width, argv[arg_index + 1]);
+		GetArgumentInteger(&height, argv[arg_index + 2]);
+		arg_index += 3;
+	}
+
+	if (argc > arg_index) {
+		/* Last parameter that was not one of the keywords must be the filename. */
+		name = argv[arg_index];
+		arg_index += 1;
+	}
+
+	if (argc > arg_index) {
+		/* We have parameters we did not process; means we misunderstood any of the above. */
+		return false;
 	}
 
-	MakeScreenshot(type, name);
+	MakeScreenshot(type, name, width, height);
 	return true;
 }
 
diff --git a/src/screenshot.cpp b/src/screenshot.cpp
index 8c64115a4..a1ad6bfad 100644
--- a/src/screenshot.cpp
+++ b/src/screenshot.cpp
@@ -710,13 +710,17 @@ static bool MakeSmallScreenshot(bool crashlog)
 /**
  * Configure a Viewport for rendering (a part of) the map into a screenshot.
  * @param t Screenshot type
+ * @param width the width of the screenshot, or 0 for current viewport width (needs to be 0 with SC_VIEWPORT, SC_CRASHLOG, and SC_WORLD).
+ * @param height the height of the screenshot, or 0 for current viewport height (needs to be 0 with SC_VIEWPORT, SC_CRASHLOG, and SC_WORLD).
  * @param[out] vp Result viewport
  */
-void SetupScreenshotViewport(ScreenshotType t, Viewport *vp)
+void SetupScreenshotViewport(ScreenshotType t, Viewport *vp, uint32 width, uint32 height)
 {
 	switch(t) {
 		case SC_VIEWPORT:
 		case SC_CRASHLOG: {
+			assert(width == 0 && height == 0);
+
 			Window *w = FindWindowById(WC_MAIN_WINDOW, 0);
 			vp->virtual_left   = w->viewport->virtual_left;
 			vp->virtual_top    = w->viewport->virtual_top;
@@ -726,12 +730,14 @@ void SetupScreenshotViewport(ScreenshotType t, Viewport *vp)
 			/* Compute pixel coordinates */
 			vp->left = 0;
 			vp->top = 0;
-			vp->width  = _screen.width;
+			vp->width = _screen.width;
 			vp->height = _screen.height;
 			vp->overlay = w->viewport->overlay;
 			break;
 		}
 		case SC_WORLD: {
+			assert(width == 0 && height == 0);
+
 			/* Determine world coordinates of screenshot */
 			vp->zoom = ZOOM_LVL_WORLD_SCREENSHOT;
 
@@ -762,8 +768,14 @@ void SetupScreenshotViewport(ScreenshotType t, Viewport *vp)
 			Window *w = FindWindowById(WC_MAIN_WINDOW, 0);
 			vp->virtual_left   = w->viewport->virtual_left;
 			vp->virtual_top    = w->viewport->virtual_top;
-			vp->virtual_width  = w->viewport->virtual_width;
-			vp->virtual_height = w->viewport->virtual_height;
+
+			if (width == 0 || height == 0) {
+				vp->virtual_width  = w->viewport->virtual_width;
+				vp->virtual_height = w->viewport->virtual_height;
+			} else {
+				vp->virtual_width = width << vp->zoom;
+				vp->virtual_height = height << vp->zoom;
+			}
 
 			/* Compute pixel coordinates */
 			vp->left = 0;
@@ -779,12 +791,14 @@ void SetupScreenshotViewport(ScreenshotType t, Viewport *vp)
 /**
  * Make a screenshot of the map.
  * @param t Screenshot type: World or viewport screenshot
+ * @param width the width of the screenshot of, or 0 for current viewport width.
+ * @param height the height of the screenshot of, or 0 for current viewport height.
  * @return true on success
  */
-static bool MakeLargeWorldScreenshot(ScreenshotType t)
+static bool MakeLargeWorldScreenshot(ScreenshotType t, uint32 width = 0, uint32 height = 0)
 {
 	Viewport vp;
-	SetupScreenshotViewport(t, &vp);
+	SetupScreenshotViewport(t, &vp, width, height);
 
 	const ScreenshotFormat *sf = _screenshot_formats + _cur_screenshot_format;
 	return sf->proc(MakeScreenshotName(SCREENSHOT_NAME, sf->extension), LargeWorldCallback, &vp, vp.width, vp.height,
@@ -877,10 +891,12 @@ void MakeScreenshotWithConfirm(ScreenshotType t)
  * Unconditionally take a screenshot of the requested type.
  * @param t    the type of screenshot to make.
  * @param name the name to give to the screenshot.
+ * @param width the width of the screenshot of, or 0 for current viewport width (only works for SC_ZOOMEDIN and SC_DEFAULTZOOM).
+ * @param height the height of the screenshot of, or 0 for current viewport height (only works for SC_ZOOMEDIN and SC_DEFAULTZOOM).
  * @return true iff the screenshot was made successfully
  * @see MakeScreenshotWithConfirm
  */
-bool MakeScreenshot(ScreenshotType t, const char *name)
+bool MakeScreenshot(ScreenshotType t, const char *name, uint32 width, uint32 height)
 {
 	VideoDriver::VideoBufferLocker lock;
 
@@ -908,6 +924,9 @@ bool MakeScreenshot(ScreenshotType t, const char *name)
 
 		case SC_ZOOMEDIN:
 		case SC_DEFAULTZOOM:
+			ret = MakeLargeWorldScreenshot(t, width, height);
+			break;
+
 		case SC_WORLD:
 			ret = MakeLargeWorldScreenshot(t);
 			break;
diff --git a/src/screenshot.h b/src/screenshot.h
index 400f8164e..148c018e1 100644
--- a/src/screenshot.h
+++ b/src/screenshot.h
@@ -25,10 +25,10 @@ enum ScreenshotType {
 	SC_MINIMAP,     ///< Minimap screenshot.
 };
 
-void SetupScreenshotViewport(ScreenshotType t, struct Viewport *vp);
+void SetupScreenshotViewport(ScreenshotType t, struct Viewport *vp, uint32 width = 0, uint32 height = 0);
 bool MakeHeightmapScreenshot(const char *filename);
 void MakeScreenshotWithConfirm(ScreenshotType t);
-bool MakeScreenshot(ScreenshotType t, const char *name);
+bool MakeScreenshot(ScreenshotType t, const char *name, uint32 width = 0, uint32 height = 0);
 bool MakeMinimapWorldScreenshot();
 
 extern char _screenshot_format_name[8];