rename built-in point shaders, SMOOTH --> AA

Updated shader names and code that uses them.

All of these shaders produce round points that are anti-aliased and blended against the background.

These were initially named SMOOTH because they replace glEnable(GL_POINT_SMOOTH). But SMOOTH in shader-land refers to vertex attribute interpolation (like glShadeModel(GL_SMOOTH)).

Using SMOOTH to mean two things is confusing, so we now use AA to mean "the point is anti-aliased".

1 files changed, 36 insertions, 0 deletions

diff --git a/source/blender/gpu/shaders/gpu_shader_point_uniform_color_outline_aa_frag.glsl b/source/blender/gpu/shaders/gpu_shader_point_uniform_color_outline_aa_frag.glsl
new file mode 100644
index 00000000000..f83785de95e
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_point_uniform_color_outline_aa_frag.glsl
@@ -0,0 +1,36 @@
+
+uniform vec4 color;
+uniform vec4 outlineColor;
+
+#if __VERSION__ == 120
+  varying vec4 radii;
+  #define fragColor gl_FragColor
+#else
+  in vec4 radii;
+  out vec4 fragColor;
+#endif
+
+void main() {
+	float dist = length(gl_PointCoord - vec2(0.5));
+
+// transparent outside of point
+// --- 0 ---
+// smooth transition
+// --- 1 ---
+// pure outline color
+// --- 2 ---
+// smooth transition
+// --- 3 ---
+// pure point color
+// ...
+// dist = 0 at center of point
+
+	float midStroke = 0.5 * (radii[1] + radii[2]);
+
+	if (dist > midStroke) {
+		fragColor.rgb = outlineColor.rgb;
+		fragColor.a = mix(outlineColor.a, 0.0, smoothstep(radii[1], radii[0], dist));
+	}
+	else
+		fragColor = mix(color, outlineColor, smoothstep(radii[3], radii[2], dist));
+}