package.path = package.path..";../../?.lua" local dirtools = require("tools.vfs.dirtools").init("sokol%-luajit") --_G.SOKOL_DLL = "sokol_debug_dll" local sapp = require("sokol_app") sg = require("sokol_gfx") local slib = require("sokol_libs") -- Warn - always after gfx!! local sshape = require("sokol_shape") local hmm = require("hmm") local hutils = require("hmm_utils") local ffi = require("ffi") -- -------------------------------------------------------------------------------------- -- The nice way to take a glsl shader and load, compile and return a shader description local shc = require("tools.shader_compiler.shc_compile").init( "sokol%-luajit", false ) -- Need to use default because this is whats used for first unnamed program local default = shc.compile("./projects/examples/samples/offscreen-sapp.glsl", "default") local offscreen = shc.compile("./projects/examples/samples/offscreen-sapp.glsl", "offscreen") -- -------------------------------------------------------------------------------------- local OFFSCREEN_PIXEL_FORMAT = (sg.SG_PIXELFORMAT_RGBA8) local OFFSCREEN_SAMPLE_COUNT = 1 local DISPLAY_SAMPLE_COUNT = 4 -- -------------------------------------------------------------------------------------- ffi.cdef[[ typedef struct state { struct { sg_pass * pass; sg_pipeline pip; sg_bindings * bind; } offscreen; struct { sg_pass_action pass_action; sg_pipeline pip; sg_bindings * bind; } display; sshape_element_range_t donut; sshape_element_range_t sphere; float rx, ry; } state; ]] local state = ffi.new("state[1]") local display_bind = ffi.new("sg_bindings[1]", {}) local offscreen_bind = ffi.new("sg_bindings[1]", {}) local off_pass = ffi.new("sg_pass[1]") -- -------------------------------------------------------------------------------------- local function init() local sg_desc = ffi.new("sg_desc[1]") sg_desc[0].environment = slib.sglue_environment() sg_desc[0].logger.func = slib.slog_func sg.sg_setup( sg_desc ) local offscreen_shader = sg.sg_make_shader(offscreen) local default_shader = sg.sg_make_shader(default) local pass_action = ffi.new("sg_pass_action[1]") pass_action[0].colors[0].load_action = sg.SG_LOADACTION_CLEAR pass_action[0].colors[0].clear_value = { 0.25, 0.45, 0.65, 1.0 } state[0].display.pass_action = pass_action[0] -- // setup a render pass struct with one color and one depth render attachment image -- // NOTE: we need to explicitly set the sample count in the attachment image objects, -- // because the offscreen pass uses a different sample count than the display render pass -- // (the display render pass is multi-sampled, the offscreen pass is not) local img_desc = ffi.new("sg_image_desc[1]") img_desc[0].render_target = true img_desc[0].width = 256 img_desc[0].height = 256 img_desc[0].pixel_format = OFFSCREEN_PIXEL_FORMAT img_desc[0].sample_count = OFFSCREEN_SAMPLE_COUNT img_desc[0].label = "color-image" local color_img = sg.sg_make_image(img_desc) img_desc[0].pixel_format = sg.SG_PIXELFORMAT_DEPTH img_desc[0].label = "depth-image"; local depth_img = sg.sg_make_image(img_desc) local att_desc = ffi.new("sg_attachments_desc[1]") att_desc[0].colors[0].image = color_img att_desc[0].depth_stencil.image = depth_img att_desc[0].label = "offscree-attachments" off_pass[0].attachments = sg.sg_make_attachments(att_desc) off_pass[0].action.colors[0].load_action = sg.SG_LOADACTION_CLEAR off_pass[0].action.colors[0].clear_value = { 0.25, 0.25, 0.25, 1.0 } off_pass[0].label = "offscreen-pass" state[0].offscreen.pass = off_pass -- // a donut shape which is rendered into the offscreen render target, and -- // a sphere shape which is rendered into the default framebuffer local vertices = ffi.new("sshape_vertex_t[4000]", {}) local indices = ffi.new("uint16_t[24000]", { 0 }) local buf = ffi.new("sshape_buffer_t[1]") buf[0].vertices.buffer.ptr = vertices buf[0].vertices.buffer.size = ffi.sizeof(vertices) buf[0].indices.buffer.ptr = indices buf[0].indices.buffer.size = ffi.sizeof(indices) local shape_torus = ffi.new("sshape_torus_t[1]", {}) shape_torus[0].radius = 0.5 shape_torus[0].ring_radius = 0.3 shape_torus[0].sides = 20 shape_torus[0].rings = 36 buf[0] = sshape.sshape_build_torus(buf, shape_torus) state[0].donut = sshape.sshape_element_range(buf) local shape_sphere = ffi.new("sshape_sphere_t[1]", {}) shape_sphere[0].radius = 0.5 shape_sphere[0].slices = 72 shape_sphere[0].stacks = 40 buf[0] = sshape.sshape_build_sphere(buf, shape_sphere) state[0].sphere = sshape.sshape_element_range(buf) local vbuf_desc = ffi.new("sg_buffer_desc[1]") vbuf_desc[0] = sshape.sshape_vertex_buffer_desc(buf) local ibuf_desc = ffi.new("sg_buffer_desc[1]") ibuf_desc[0] = sshape.sshape_index_buffer_desc(buf) vbuf_desc[0].label = "shape-vbuf" ibuf_desc[0].label = "shape-ibuf" local vbuf = sg.sg_make_buffer(vbuf_desc) local ibuf = sg.sg_make_buffer(ibuf_desc) -- // pipeline-state-object for offscreen-rendered donut -- // NOTE: we need to explicitly set the sample_count here because -- // the offscreen pass uses a different sample count than the default -- // pass (the display pass is multi-sampled, but the offscreen pass isn't) local pipeline = ffi.new("sg_pipeline_desc[1]") pipeline[0].layout.buffers[0] = sshape.sshape_vertex_buffer_layout_state() pipeline[0].layout.attrs[0] = sshape.sshape_position_vertex_attr_state() pipeline[0].layout.attrs[1] = sshape.sshape_normal_vertex_attr_state() pipeline[0].shader = offscreen_shader pipeline[0].index_type = sg.SG_INDEXTYPE_UINT16 pipeline[0].cull_mode = sg.SG_CULLMODE_BACK pipeline[0].sample_count = OFFSCREEN_SAMPLE_COUNT pipeline[0].depth.pixel_format = sg.SG_PIXELFORMAT_DEPTH pipeline[0].depth.compare = sg.SG_COMPAREFUNC_LESS_EQUAL pipeline[0].depth.write_enabled = true pipeline[0].colors[0].pixel_format = OFFSCREEN_PIXEL_FORMAT pipeline[0].label = "offscreen-pipeline" state[0].offscreen.pip = sg.sg_make_pipeline(pipeline) -- // and another pipeline-state-object for the default pass local pipe_desc = ffi.new("sg_pipeline_desc[1]") pipe_desc[0].layout.buffers[0] = sshape.sshape_vertex_buffer_layout_state() pipe_desc[0].layout.attrs[0] = sshape.sshape_position_vertex_attr_state() pipe_desc[0].layout.attrs[1] = sshape.sshape_normal_vertex_attr_state() pipe_desc[0].layout.attrs[2] = sshape.sshape_texcoord_vertex_attr_state() pipe_desc[0].shader = default_shader pipe_desc[0].index_type = sg.SG_INDEXTYPE_UINT16 pipe_desc[0].cull_mode = sg.SG_CULLMODE_BACK pipe_desc[0].depth.compare = sg.SG_COMPAREFUNC_LESS_EQUAL pipe_desc[0].depth.write_enabled = true pipe_desc[0].label = "default-pipeline" state[0].display.pip = sg.sg_make_pipeline(pipe_desc) -- // a sampler object for sampling the render target texture local sampler = ffi.new("sg_sampler_desc[1]") sampler[0].min_filter = sg.SG_FILTER_LINEAR sampler[0].mag_filter = sg.SG_FILTER_LINEAR sampler[0].wrap_u = sg.SG_WRAP_REPEAT sampler[0].wrap_v = sg.SG_WRAP_REPEAT local smp = sg.sg_make_sampler(sampler) -- // the resource bindings for rendering a non-textured shape into offscreen render target offscreen_bind[0].vertex_buffers[0] = vbuf offscreen_bind[0].index_buffer = ibuf state[0].offscreen.bind = offscreen_bind -- // resource bindings to render a textured shape, using the offscreen render target as texture display_bind[0].vertex_buffers[0] = vbuf display_bind[0].index_buffer = ibuf display_bind[0].images[0] = color_img display_bind[0].samplers[0] = smp state[0].display.bind = display_bind end -- -------------------------------------------------------------------------------------- -- // helper function to compute model-view-projection matrix local function compute_mvp( rx, ry, aspect, eye_dist) local proj = hmm.HMM_Perspective(45.0, aspect, 0.01, 10.0) local view = hmm.HMM_LookAt(hmm.HMM_Vec3(0.0, 0.0, eye_dist), hmm.HMM_Vec3(0.0, 0.0, 0.0), hmm.HMM_Vec3(0.0, 1.0, 0.0)) local view_proj = hmm.HMM_MultiplyMat4(proj, view) local rxm = hmm.HMM_Rotate(rx, hmm.HMM_Vec3(1.0, 0.0, 0.0)) local rym = hmm.HMM_Rotate(ry, hmm.HMM_Vec3(0.0, 1.0, 0.0)) local model = hmm.HMM_MultiplyMat4(rym, rxm) local mvp = hmm.HMM_MultiplyMat4(view_proj, model) return mvp end -- -------------------------------------------------------------------------------------- local vs_params = ffi.new("vs_params_t[1]") local def_vs_params = ffi.new("vs_params_t[1]") local vs_range = ffi.new("sg_range[1]") local def_vs_range = ffi.new("sg_range[1]") local function frame() local t = (sapp.sapp_frame_duration() * 60.0) state[0].rx = state[0].rx + 1.0 * t state[0].ry = state[0].ry + 2.0 * t -- // the offscreen pass, rendering an rotating, untextured donut into a render target image vs_params[0].mvp = compute_mvp(state[0].rx, state[0].ry, 1.0, 2.5) vs_range[0].ptr = vs_params vs_range[0].size = ffi.sizeof(vs_params) sg.sg_begin_pass(state[0].offscreen.pass) sg.sg_apply_pipeline(state[0].offscreen.pip) sg.sg_apply_bindings(state[0].offscreen.bind) sg.sg_apply_uniforms(sg.SG_SHADERSTAGE_VS, vs_range) sg.sg_draw(state[0].donut.base_element, state[0].donut.num_elements, 1) sg.sg_end_pass() -- // and the display-pass, rendering a rotating textured sphere which uses the -- // previously rendered offscreen render-target as texture local w = sapp.sapp_width() local h = sapp.sapp_height() def_vs_params[0].mvp = compute_mvp(-state[0].rx * 0.25, state[0].ry * 0.25, w/h, 3.0) local pass = ffi.new("sg_pass[1]") pass[0].action = state[0].display.pass_action pass[0].swapchain = slib.sglue_swapchain() pass[0].label = "swapchain-pass" sg.sg_begin_pass(pass) def_vs_range[0].ptr = def_vs_params def_vs_range[0].size = ffi.sizeof(def_vs_params) sg.sg_apply_pipeline(state[0].display.pip) sg.sg_apply_bindings(state[0].display.bind) sg.sg_apply_uniforms(sg.SG_SHADERSTAGE_VS, def_vs_range) sg.sg_draw(state[0].sphere.base_element, state[0].sphere.num_elements, 1) sg.sg_end_pass() sg.sg_commit() -- Display frame stats in console. -- hutils.show_stats() end -- -------------------------------------------------------------------------------------- local function cleanup() sg.sg_shutdown() end -- -------------------------------------------------------------------------------------- local app_desc = ffi.new("sapp_desc[1]") app_desc[0].init_cb = init app_desc[0].frame_cb = frame app_desc[0].cleanup_cb = cleanup app_desc[0].width = 1920 app_desc[0].height = 1080 app_desc[0].sample_count = DISPLAY_SAMPLE_COUNT app_desc[0].window_title = "Offscreen (sokol-app)" app_desc[0].icon.sokol_default = true app_desc[0].logger.func = slib.slog_func sapp.sapp_run( app_desc ) -- --------------------------------------------------------------------------------------