first build attempt

build/shaders/bloom.vert

@@ -0,0 +1,20 @@
+/*
+ * MIT License
+ * Author: Mark Allyn
+ *
+ * bloom.vert — vertex shader for the bloom post-processing pass.
+ * Identical to sweep.vert: fullscreen clip-space quad with UV passthrough.
+ * The actual bloom is currently implemented inline in phosphor.frag;
+ * this shader is reserved for a separate two-pass Gaussian bloom
+ * if higher quality is required in a future revision.
+ */
+#version 330 core
+
+layout(location = 0) in vec2 aPos;
+
+out vec2 vTexCoord;
+
+void main() {
+    gl_Position = vec4(aPos, 0.0, 1.0);
+    vTexCoord   = aPos * 0.5 + 0.5;
+}