From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Wed, 11 Mar 2015 13:50:10 +0000 (+0100)
Subject: control (some) application parameters via cmdline
X-Git-Url: http://git.localhorst.tv/?a=commitdiff_plain;h=f01ebd81ff047eb3209e25e183564f72f587915f;p=blank.git

control (some) application parameters via cmdline
---

diff --git a/building b/building
index 4163862..e10bb28 100644
--- a/building
+++ b/building
@@ -46,3 +46,19 @@ CPPFLAGS, CXXFLAGS, LDXXFLAGS:
 
 DEBUG_FLAGS, PROFILE_FLAGS, RELEASE_FLAGS:
 	flags for building binaries in debug, profile, and release mode
+
+
+Running
+=======
+
+blank
+	normal execution
+
+blank <n>
+	terminate after <n> frames
+
+blank -t <t>
+	terminate after <t> milliseconds
+
+blank <n> -t <t>
+	terminate after n frames, assume <t> milliseconds pass each frame
diff --git a/src/app.cpp b/src/app.cpp
index d8f1e21..7ddbbf1 100644
--- a/src/app.cpp
+++ b/src/app.cpp
@@ -40,6 +40,34 @@ Application::Application()
 }
 
 
+void Application::RunN(size_t n) {
+	Uint32 last = SDL_GetTicks();
+	for (size_t i = 0; i < n; ++i) {
+		Uint32 now = SDL_GetTicks();
+		int delta = now - last;
+		Loop(delta);
+		last = now;
+	}
+}
+
+void Application::RunT(size_t t) {
+	Uint32 last = SDL_GetTicks();
+	Uint32 finish = last + t;
+	while (last < finish) {
+		Uint32 now = SDL_GetTicks();
+		int delta = now - last;
+		Loop(delta);
+		last = now;
+	}
+}
+
+void Application::RunS(size_t n, size_t t) {
+	for (size_t i = 0; i < n; ++i) {
+		Loop(t);
+	}
+}
+
+
 void Application::Run() {
 	running = true;
 	Uint32 last = SDL_GetTicks();
diff --git a/src/app.hpp b/src/app.hpp
index 0b0e64e..cb71411 100644
--- a/src/app.hpp
+++ b/src/app.hpp
@@ -23,9 +23,17 @@ public:
 	Application(const Application &) = delete;
 	Application &operator =(const Application &) = delete;
 
+	/// run until user quits
 	void Run();
 	void Loop(int dt);
 
+	/// run for n frames
+	void RunN(size_t n);
+	/// run for t milliseconds
+	void RunT(size_t t);
+	/// run for n frames, assuming t milliseconds for each
+	void RunS(size_t n, size_t t);
+
 	void HandleEvents();
 	void Update(int dt);
 	void Render();
diff --git a/src/main.cpp b/src/main.cpp
index 06771fe..f9bc154 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,12 +1,85 @@
 #include "app.hpp"
 
+#include <cctype>
+#include <cstdlib>
+#include <iostream>
+
 using namespace blank;
 
 
+namespace {
+
+enum Mode {
+	NORMAL,
+	FRAME_LIMIT,
+	TIME_LIMIT,
+	FIXED_FRAME_LIMIT,
+};
+
+}
+
+
 int main(int argc, char *argv[]) {
 
+	Mode mode = NORMAL;
+	size_t n = 0, t = 0;
+
+	bool error = false;
+	for (int i = 1; i < argc; ++i) {
+		if (argv[i] == nullptr || argv[i][0] == '\0') continue;
+		if (argv[i][0] == '-') {
+			if (argv[i][1] == 't' && argv[i][2] == '\0') {
+				++i;
+				if (i >= argc) {
+					std::cerr << "missing argument to -t" << std::endl;
+					error = true;
+				} else {
+					t = std::strtoul(argv[i], nullptr, 10);
+				}
+			} else {
+				std::cerr << "unable to interpret argument "
+					<< i << " (" << argv[i] << ")" << std::endl;
+				error = true;
+			}
+		} else if (std::isdigit(*argv[i])) {
+			n = std::strtoul(argv[i], nullptr, 10);
+		} else {
+			std::cerr << "unable to interpret argument "
+				<< i << " (" << argv[i] << ")" << std::endl;
+			error = true;
+		}
+	}
+
+	if (error) {
+		return 1;
+	}
+
+	if (n > 0) {
+		if (t > 0) {
+			mode = FIXED_FRAME_LIMIT;
+		} else {
+			mode = FRAME_LIMIT;
+		}
+	} else if (t > 0) {
+		mode = TIME_LIMIT;
+	}
+
 	Application app;
-	app.Run();
+	switch (mode) {
+		default:
+		case NORMAL:
+			app.Run();
+			break;
+		case FRAME_LIMIT:
+			app.RunN(n);
+			break;
+		case TIME_LIMIT:
+			app.RunT(t);
+			break;
+		case FIXED_FRAME_LIMIT:
+			app.RunS(n, t);
+			break;
+	}
 
 	return 0;