Explicitly declare use of round() as an #extension.

[movit] / init.cpp

diff --git a/init.cpp b/init.cpp
index df72832e7b63985b50deb266db289d2ade015ef5..d8d249f256203decf638fb92febea1f44e758bdc 100644 (file)
--- a/init.cpp
+++ b/init.cpp
@@ -14,6 +14,7 @@ MovitDebugLevel movit_debug_level = MOVIT_DEBUG_ON;
 float movit_texel_subpixel_precision;
 bool movit_srgb_textures_supported;
 int movit_num_wrongly_rounded;
+bool movit_shader_rounding_supported;
 
 // The rules for objects with nontrivial constructors in static scope
 // are somewhat convoluted, and easy to mess up. We simply have a
@@ -273,6 +274,12 @@ void check_extensions()
        // sRGB texture decode would be nice, but are not mandatory
        // (GammaExpansionEffect can do the same thing if needed).
        movit_srgb_textures_supported = glewIsSupported("GL_EXT_texture_sRGB");
+
+       // We may want to use round() at the end of the final shader,
+       // if supported. We need either GLSL 1.30 or this extension to do that,
+       // and 1.30 brings with it other things that we don't want to demand
+       // for now.
+       movit_shader_rounding_supported = glewIsSupported("GL_EXT_gpu_shader4");
 }
 
 }  // namespace