Add ktx

ktx/tests/loadtests/appfwSDL/VulkanAppSDL/shaders/textoverlay.frag

@@ -0,0 +1,16 @@
+// Copyright 2017-2020 Mark Callow
+// SPDX-License-Identifier: Apache-2.0
+
+#version 450 core
+
+layout (location = 0) in vec2 inUV;
+
+layout (binding = 0) uniform sampler2D samplerFont;
+
+layout (location = 0) out vec4 outFragColor;
+
+void main(void)
+{
+	float color = texture(samplerFont, inUV).r;
+	outFragColor = vec4(vec3(color), 1.0);
+}

ktx/tests/loadtests/appfwSDL/VulkanAppSDL/shaders/textoverlay.vert

@@ -0,0 +1,20 @@
+// Copyright 2017-2020 Mark Callow
+// SPDX-License-Identifier: Apache-2.0
+
+#version 450 core
+
+layout (location = 0) in vec2 inPos;
+layout (location = 1) in vec2 inUV;
+
+layout (location = 0) out vec2 outUV;
+
+out gl_PerVertex
+{
+    vec4 gl_Position;
+};
+
+void main(void)
+{
+	gl_Position = vec4(inPos, 0.0, 1.0);
+	outUV = inUV;
+}