From 489036a40cc3c9f41109fac61de3257acf99d3ef Mon Sep 17 00:00:00 2001
From: omigamedev <omarator@gmail.com>
Date: Wed, 30 Jan 2019 14:00:56 +0100
Subject: [PATCH] use glsl built-in ifdef directive for extensions

---
 src/app_shaders.cpp | 44 ++++++++++++++++++++++----------------------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/src/app_shaders.cpp b/src/app_shaders.cpp
index aea545c..4283abd 100644
--- a/src/app_shaders.cpp
+++ b/src/app_shaders.cpp
@@ -85,27 +85,27 @@ void App::initShaders()
         "}\n";
     static const char* shader_blend_f =
         SHADER_VERSION
-#ifdef __IOS__
-        "#extension GL_EXT_shader_framebuffer_fetch : enable\n"
-#endif
+        "#if defined(GL_EXT_shader_framebuffer_fetch)\n"
+        "   #extension GL_EXT_shader_framebuffer_fetch : enable\n"
+        "#endif\n"
         "uniform sampler2D tex;\n"
         "uniform sampler2D tex_alpha;\n"
         "uniform sampler2D tex_bg;\n"
         "uniform mediump float alpha;\n"
         "uniform int blend_mode;\n"
         "in mediump vec2 uv;\n"
-#ifdef __IOS__
-        "inout highp vec4 frag;\n"
-#else
-        "out mediump vec4 frag;\n"
-#endif
+        "#if defined(GL_EXT_shader_framebuffer_fetch)\n"
+        "   inout highp vec4 frag;\n"
+        "#else\n"
+        "   out mediump vec4 frag;\n"
+        "#endif\n"
         SHADER_FUNCTION_BLEND
         "void main() {\n"
-#ifdef __IOS__
+        "#if defined(GL_EXT_shader_framebuffer_fetch)\n"
         "   highp vec4 bg = frag;\n"
-#else
+        "#else\n"
         "   mediump vec4 bg = texture(tex_bg, uv);\n"
-#endif
+        "#endif\n"
         "   mediump vec4 fg = vec4(texture(tex, uv).rgb, texture(tex_alpha, uv).a);\n"
         "   if (fg.a == 0.0) { frag = bg; return; }\n"
         "   mediump float contribution = (1.0 - bg.a) * fg.a;\n"
@@ -357,9 +357,9 @@ void App::initShaders()
         "}\n";
     static const char* shader_stroke_f =
         SHADER_VERSION
-#ifdef __IOS__
-        "#extension GL_EXT_shader_framebuffer_fetch : enable\n"
-#endif
+        "#if defined(GL_EXT_shader_framebuffer_fetch)\n"
+        "   #extension GL_EXT_shader_framebuffer_fetch : enable\n"
+        "#endif\n"
         "uniform mediump sampler2D tex;\n"
         "uniform mediump sampler2D tex_bg;\n"
         "uniform mediump sampler2D tex_stencil;\n"
@@ -375,22 +375,22 @@ void App::initShaders()
         "in mediump vec2 uv;\n"
         "in mediump vec2 uv_2;\n"
         "in mediump float q;\n"
-#ifdef __IOS__
-        "inout mediump vec4 frag;\n"
-#else
-        "out mediump vec4 frag;\n"
-#endif
+        "#if defined(GL_EXT_shader_framebuffer_fetch)\n"
+        "   inout mediump vec4 frag;\n"
+        "#else\n"
+        "   out mediump vec4 frag;\n"
+        "#endif\n"
         SHADER_FUNCTION_RAND
         "void main() {\n"
         "   mediump vec2 uv2 = gl_FragCoord.st / resolution;\n"
         "   mediump float stencil = 1.0 - (texture(tex_stencil, (uv2+stencil_offset) * 5.0).r) * stencil_alpha;\n"
         "   mediump float brush_alpha = ( 1.0 - texture(tex, uv/q).r ) * alpha;\n"
         "   mediump vec4 fg = vec4(col.rgb, brush_alpha * stencil);\n"
-#ifdef __IOS__
+        "#if defined(GL_EXT_shader_framebuffer_fetch)\n"
         "   mediump vec4 bg = frag;\n"
-#else
+        "#else\n"
         "   mediump vec4 bg = texture(tex_bg, uv2);\n"
-#endif
+        "#endif\n"
         "   fg.a *= 1.0-rand(uv2+uv)*noise;\n"
         "   if (fg.a == 0.0) discard;\n"
         "   if (mix_alpha > 0.0){\n"