From 01547a0a2051465fc6088e0d463c2d7959f5d61d Mon Sep 17 00:00:00 2001
From: Sam Hocevar <sam@hocevar.net>
Date: Sat, 29 Jun 2013 14:29:20 +0000
Subject: [PATCH] gpu: add a 16-bit depth buffer to framebuffers on WebGL and
 GL ES.

---
 src/gpu/framebuffer.cpp | 18 +++++++++++++-----
 src/lolgl.h             |  6 ++++++
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/gpu/framebuffer.cpp b/src/gpu/framebuffer.cpp
index 7d3fa70d..e66a9d95 100644
--- a/src/gpu/framebuffer.cpp
+++ b/src/gpu/framebuffer.cpp
@@ -344,12 +344,17 @@ Framebuffer::Framebuffer(ivec2 size, FramebufferFormat fbo_format)
      * GL_RGBA16F_ARB, GL_RGB32F_ARB, GL_RGBA32F_ARB, GL_LUMINANCE32F_ARB. */
     GLenum internal_format = fbo_format.GetFormat();
     GLenum format = fbo_format.GetFormatOrder();
+#   elif GL_ES_VERSION_2_0
+    /* In OpenGL ES, internal format and format must match. */
+    GLenum internal_format = fbo_format.GetFormat();
+    GLenum format = fbo_format.GetFormat();
+    GLenum depth = GL_DEPTH_COMPONENT16; /* for WebGL */
 #   else
     /* In OpenGL ES, internal format and format must match. */
     GLenum internal_format = fbo_format.GetFormat();
     GLenum format = fbo_format.GetFormat();
 #   endif
-    GLenum wrapmode = GL_REPEAT;
+    GLenum wrapmode = GL_CLAMP_TO_EDGE;
     GLenum filtering = GL_NEAREST;
 
 #   if GL_VERSION_1_1 || GL_ES_VERSION_2_0
@@ -379,11 +384,12 @@ Framebuffer::Framebuffer(ivec2 size, FramebufferFormat fbo_format)
 #   endif
 
     m_data->m_depth = GL_INVALID_ENUM;
-#   if GL_VERSION_1_1
-    /* FIXME: not implemented on GL ES, see
-     * http://stackoverflow.com/q/4041682/111461 */
+#   if GL_VERSION_1_1 || GL_ES_VERSION_2_0
     if (depth != GL_INVALID_ENUM)
     {
+        /* XXX: might not work on GL ES, see
+         * http://stackoverflow.com/q/4041682/111461
+         * See also http://qt-project.org/forums/viewthread/11734 */
         glGenRenderbuffers(1, &m_data->m_depth);
         glBindRenderbuffer(GL_RENDERBUFFER, m_data->m_depth);
         glRenderbufferStorage(GL_RENDERBUFFER, depth, size.x, size.y);
@@ -392,6 +398,8 @@ Framebuffer::Framebuffer(ivec2 size, FramebufferFormat fbo_format)
     }
 #   endif
 
+    glBindTexture(GL_TEXTURE_2D, 0);
+
 #   if GL_VERSION_1_1 || GL_ES_VERSION_2_0
     GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
     ASSERT(status == GL_FRAMEBUFFER_COMPLETE,
@@ -418,7 +426,7 @@ Framebuffer::~Framebuffer()
     glDeleteFramebuffersOES(1, &m_data->m_fbo);
 #   endif
     glDeleteTextures(1, &m_data->m_texture);
-#   if GL_VERSION_1_1
+#   if GL_VERSION_1_1 || GL_ES_VERSION_2_0
     if (m_data->m_depth != GL_INVALID_ENUM)
         glDeleteRenderbuffers(1, &m_data->m_depth);
 #   endif
diff --git a/src/lolgl.h b/src/lolgl.h
index 1878a64d..5340ae35 100644
--- a/src/lolgl.h
+++ b/src/lolgl.h
@@ -59,5 +59,11 @@
 #   endif
 #endif
 
+#define LOL_CHECK_GLERROR() \
+    { \
+        GLenum error = glGetError(); \
+        ASSERT(error == GL_NO_ERROR, "OpenGL error: 0x%04x\n", error); \
+    }
+
 #endif // __LOL_LOLGL_H__