+// Same, but with a depth texture.
+template<size_t num_elements>
+class PersistentFBOSetWithDepth {
+public:
+ void render_to(GLuint depth_tex, const array<GLuint, num_elements> &textures);
+
+ // Convenience wrappers.
+ void render_to(GLuint depth_tex, GLuint texture0) {
+ render_to(depth_tex, {{texture0}});
+ }
+
+ void render_to(GLuint depth_tex, GLuint texture0, GLuint texture1) {
+ render_to(depth_tex, {{texture0, texture1}});
+ }
+
+ void render_to(GLuint depth_tex, GLuint texture0, GLuint texture1, GLuint texture2) {
+ render_to(depth_tex, {{texture0, texture1, texture2}});
+ }
+
+ void render_to(GLuint depth_tex, GLuint texture0, GLuint texture1, GLuint texture2, GLuint texture3) {
+ render_to(depth_tex, {{texture0, texture1, texture2, texture3}});
+ }
+
+private:
+ // TODO: Delete these on destruction.
+ map<pair<GLuint, array<GLuint, num_elements>>, GLuint> fbos;
+};
+
+template<size_t num_elements>
+void PersistentFBOSetWithDepth<num_elements>::render_to(GLuint depth_tex, const array<GLuint, num_elements> &textures)
+{
+ auto key = make_pair(depth_tex, textures);
+
+ auto it = fbos.find(key);
+ if (it != fbos.end()) {
+ glBindFramebuffer(GL_FRAMEBUFFER, it->second);
+ return;
+ }
+
+ GLuint fbo;
+ glCreateFramebuffers(1, &fbo);
+ GLenum bufs[num_elements];
+ glNamedFramebufferTexture(fbo, GL_DEPTH_ATTACHMENT, depth_tex, 0);
+ for (size_t i = 0; i < num_elements; ++i) {
+ glNamedFramebufferTexture(fbo, GL_COLOR_ATTACHMENT0 + i, textures[i], 0);
+ bufs[i] = GL_COLOR_ATTACHMENT0 + i;
+ }
+ glNamedFramebufferDrawBuffers(fbo, num_elements, bufs);
+
+ fbos[key] = fbo;
+ glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+}
+