From a21520508fe04919e7776ba2a243ac8a1f02f4dc Mon Sep 17 00:00:00 2001
From: Maya Woodward <mayawoodward0@gmail.com>
Date: Fri, 15 Sep 2023 00:07:58 -0400
Subject: [PATCH] Add compile_flags, merge engine code into working emscripten
 build

---
 Makefile          | 29 +++++++++++++++++++++--------
 README.md         |  6 ++++++
 compile_flags.txt |  6 ++++++
 src/vestige.c     | 37 +++++++++++++++++++++++++++++--------
 4 files changed, 62 insertions(+), 16 deletions(-)
 create mode 100644 compile_flags.txt

diff --git a/Makefile b/Makefile
index a6b2d96..24991da 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,4 @@
-TARGET=vestige
-
-CC=clang
+TARGET?=native
 
 BUILD_DIR:=./build
 SRC_DIRS:=./src
@@ -12,16 +10,31 @@ DEPS:=$(OBJS:.o=.d)
 INC_DIRS:=./include $(shell find $(SRC_DIRS) -type d)
 INC_FLAGS:=$(addprefix -I,$(INC_DIRS))
 
-CFLAGS:=$(INC_FLAGS) -std=c17 -Wall -Wpedantic -Werror -O2 -MMD -MP
-
 LDFLAGS:=-lglfw -lGL
+CFLAGS:=$(INC_FLAGS) -std=c17 -Wall -Wpedantic -Werror -O2 -MMD -MP -g
+
+ifeq ($(TARGET),web)
+	CC:=emcc
+	LDFLAGS:=$(LDFLAGS) -O2 --emrun -s USE_GLFW=3 -s FULL_ES3
+	TARGET_EXEC=vestige.html
+else
+	CC:=clang
+	TARGET_EXEC=vestige
+endif
 
 .PHONY: clean
 
-all: $(BUILD_DIR)/$(TARGET)
+all: $(BUILD_DIR)/$(TARGET_EXEC)
+
+run: $(BUILD_DIR)/$(TARGET_EXEC)
+ifeq ($(TARGET),web)
+	emrun $(BUILD_DIR)/$(TARGET_EXEC)
+else
+	./$(BUILD_DIR)/$(TARGET_EXEC)
+endif
 
-$(BUILD_DIR)/$(TARGET): $(OBJS)
-	$(CC) $(OBJS) -o $@ $(LDFLAGS)
+$(BUILD_DIR)/$(TARGET_EXEC): $(OBJS)
+	$(CC) $(LDFLAGS) $(OBJS) -o $@
 
 $(BUILD_DIR)/%.c.o: %.c
 	mkdir -p $(dir $@)
diff --git a/README.md b/README.md
index 94aaace..16c66af 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,7 @@
 # Vestige Engine
+
+## Building
+
+### Dependencies
+
+* [Emscripten=3.1.45](https://emscripten.org/docs/getting_started/downloads.html#sdk-download-and-install)
diff --git a/compile_flags.txt b/compile_flags.txt
new file mode 100644
index 0000000..679ebcf
--- /dev/null
+++ b/compile_flags.txt
@@ -0,0 +1,6 @@
+-std=c17
+-Wall
+-Wpedantic
+-Werror
+-I./src
+-I./include
diff --git a/src/vestige.c b/src/vestige.c
index 11ee9da..a63928f 100644
--- a/src/vestige.c
+++ b/src/vestige.c
@@ -1,27 +1,48 @@
+#include <stdio.h>
+
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#endif
 #include <GLFW/glfw3.h>
+
 #include "window.h"
 #include "engine.h"
-#include <stdio.h>
+
+GLFWwindow* APP = NULL;
+
+static void main_loop(void) {
+    glClear(GL_COLOR_BUFFER_BIT);
+    glfwSwapBuffers(APP);
+    glfwPollEvents();
+}
 
 int main(int argc, char* argv[]) {
     engine_start();
+
     if (!glfwInit()) {
+        printf("Failed to initialize GLFW!\n");
         return 1;
     }
 
-    GLFWwindow* app = glfwCreateWindow(640, 480, "Hello, Window!", NULL, NULL);
-    if (!app) {
+    APP = glfwCreateWindow(640, 480, "Hello, Window!", NULL, NULL);
+    if (!APP) {
         glfwTerminate();
         return 1;
     }
 
-    glfwMakeContextCurrent(app);
+    glfwMakeContextCurrent(APP);
+
+    glfwSwapInterval(1);
+
+    glClearColor(255, 0, 0, 255);
 
-    while (!glfwWindowShouldClose(app)) {
-        glClear(GL_COLOR_BUFFER_BIT);
-        glfwSwapBuffers(app);
-        glfwPollEvents();
+#ifdef __EMSCRIPTEN__
+    emscripten_set_main_loop(main_loop, 0, 1);
+#else
+    while (!glfwWindowShouldClose(APP)) {
+        main_loop();
     }
+#endif
 
     glfwTerminate();