examples: add render-pass-ext exmaple

examples/render-pass-ext/vulkan/shaders/meson.build

@@ -0,0 +1,24 @@
+vulkan_custom_shaders_src = [
+	'triangle.vert',
+	'triangle.frag',
+]
+
+vulkan_shader_sources = []
+foreach shader : vulkan_custom_shaders_src
+	if shader == 'triangle.vert'
+		name = 'custom_triangle_vert_data'
+	else
+		name = 'custom_triangle_frag_data'
+	endif
+	args = [glslang, '-V', '@INPUT@', '-o', '@OUTPUT@', '--vn', name]
+	if glslang_version.version_compare('>=11.0.0')
+		args += '--quiet'
+	endif
+	header = custom_target(
+		'custom-render-pass-vulkan-' + shader + '_spv',
+		output: shader + '.h',
+		input: shader,
+		command: args,
+	)
+	vulkan_shader_sources += [header]
+endforeach

examples/render-pass-ext/vulkan/shaders/triangle.frag

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+#version 450
+
+layout(location = 0) in vec3 v_color;
+layout(location = 0) out vec4 out_color;
+
+void main() {
+	out_color = vec4(v_color, 1.0);
+}

examples/render-pass-ext/vulkan/shaders/triangle.vert

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+#version 450
+
+// Keep push constants layout compatible with wlroots Vulkan helpers.
+layout(push_constant, row_major) uniform UBO {
+	mat4 proj;
+	vec4 pos[3];
+	vec4 color[3];
+} data;
+
+layout(location = 0) out vec3 v_color;
+
+void main() {
+	gl_Position = data.proj * vec4(data.pos[gl_VertexIndex].xy, 0.0, 1.0);
+	v_color = data.color[gl_VertexIndex].rgb;
+}