OpenGL: prepare GLSL for version 3.3

- use in/out instead of attribute/varying
- use named output instead of gl_FragColor
- use texture() instead of the multitude of older texture sampling functions

The #if __VERSION__ == 120 paths (needed on Mac) will be removed after we switch to 3.3 core profile.

Part of T49165 (general OpenGL upgrade)

1 files changed, 10 insertions, 2 deletions

diff --git a/source/blender/gpu/shaders/gpu_shader_fire_frag.glsl b/source/blender/gpu/shaders/gpu_shader_fire_frag.glsl
index 3819203bcd9..45f86e036a1 100644
--- a/source/blender/gpu/shaders/gpu_shader_fire_frag.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_fire_frag.glsl
@@ -1,5 +1,13 @@
 
-varying vec3 coords;
+#if __VERSION__ == 120
+  varying vec3 coords;
+  #define fragColor gl_FragColor
+#else
+  in vec3 coords;
+  out vec4 fragColor;
+  #define texture1D texture
+  #define texture3D texture
+#endif
 
 uniform sampler3D flame_texture;
 uniform sampler1D spectrum_texture;
@@ -13,5 +21,5 @@ void main()
 	color.rgb = emission.a * emission.rgb;
 	color.a = emission.a;
 
-	gl_FragColor = color;
+	fragColor = color;
 }