From 9f4a441bf16fa5bc79bdf33f9e2194b3fe11a09c Mon Sep 17 00:00:00 2001
From: bjorn <tie.372@gmail.com>
Date: Thu, 24 Nov 2016 15:45:59 -0800
Subject: [PATCH] Allow disabling of depth test;

---
 src/glfw.c              |  1 -
 src/graphics/graphics.c |  6 ++++++
 src/graphics/graphics.h |  1 +
 src/lovr/graphics.c     | 15 ++++++++++++---
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/glfw.c b/src/glfw.c
index 4f7c2a08..5b6a7375 100644
--- a/src/glfw.c
+++ b/src/glfw.c
@@ -42,5 +42,4 @@ void initGlfw(GLFWerrorfun onError, GLFWwindowclosefun onClose, void* userPointe
   glEnable(GL_BLEND);
   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
   glEnable(GL_LINE_SMOOTH);
-  glEnable(GL_DEPTH_TEST);
 }
diff --git a/src/graphics/graphics.c b/src/graphics/graphics.c
index 3c273912..989c60ba 100644
--- a/src/graphics/graphics.c
+++ b/src/graphics/graphics.c
@@ -22,6 +22,7 @@ void lovrGraphicsInit() {
   glGenVertexArrays(1, &state.shapeArray);
   vec_init(&state.shapeData);
   vec_init(&state.shapeIndices);
+  state.depthTest = -1;
   lovrGraphicsReset();
 }
 
@@ -235,6 +236,11 @@ void lovrGraphicsSetDepthTest(CompareMode depthTest) {
   if (state.depthTest != depthTest) {
     state.depthTest = depthTest;
     glDepthFunc(depthTest);
+    if (depthTest) {
+      glEnable(GL_DEPTH_TEST);
+    } else {
+      glDisable(GL_DEPTH_TEST);
+    }
   }
 }
 
diff --git a/src/graphics/graphics.h b/src/graphics/graphics.h
index 4fe42e26..0b5a0629 100644
--- a/src/graphics/graphics.h
+++ b/src/graphics/graphics.h
@@ -25,6 +25,7 @@ typedef enum {
 } PolygonWinding;
 
 typedef enum {
+  COMPARE_NONE = 0,
   COMPARE_EQUAL = GL_EQUAL,
   COMPARE_NOT_EQUAL = GL_NOTEQUAL,
   COMPARE_LESS = GL_LESS,
diff --git a/src/lovr/graphics.c b/src/lovr/graphics.c
index 71e97ab6..07ea230e 100644
--- a/src/lovr/graphics.c
+++ b/src/lovr/graphics.c
@@ -327,13 +327,22 @@ int l_lovrGraphicsSetPolygonWinding(lua_State* L) {
 }
 
 int l_lovrGraphicsGetDepthTest(lua_State* L) {
-  lua_pushstring(L, map_int_find(&CompareModes, lovrGraphicsGetDepthTest()));
+  CompareMode depthTest = lovrGraphicsGetDepthTest();
+  if (depthTest) {
+    lua_pushstring(L, map_int_find(&CompareModes, depthTest));
+  } else {
+    lua_pushnil(L);
+  }
   return 1;
 }
 
 int l_lovrGraphicsSetDepthTest(lua_State* L) {
-  CompareMode* depthTest = (CompareMode*) luax_checkenum(L, 1, &CompareModes, "compare mode");
-  lovrGraphicsSetDepthTest(*depthTest);
+  if (lua_isnoneornil(L, 1)) {
+    lovrGraphicsSetDepthTest(COMPARE_NONE);
+  } else {
+    CompareMode* depthTest = (CompareMode*) luax_checkenum(L, 1, &CompareModes, "compare mode");
+    lovrGraphicsSetDepthTest(*depthTest);
+  }
   return 0;
 }