Add clear_screen sample.

clear_screen/clear_screen.c

@@ -0,0 +1,85 @@
+#include <assert.h>
+#include <stdio.h>
+#include <emscripten/em_math.h>
+#include "lib_webgpu.h"
+
+WGpuAdapter adapter;
+WGpuSwapChain swapChain;
+WGpuDevice device;
+WGpuQueue defaultQueue;
+
+double hue2rgb(double v1, double v2, double vh)
+{
+  if (vh < 0.0) vh += 1.0;
+  if (vh > 1.0) vh -= 1.0;
+  if (vh < 1.0 / 6.0) return v1 + (v2 - v1) * 6.0 * vh;
+  if (vh < 1.0 / 2.0) return v2;
+  if (vh < 2.0 / 3.0) return v1 + (v2 - v1) * (2.0 / 3.0 - vh) * 6.0;
+  return v1;
+}
+
+void hsl2rgb(double hue, double saturation, double luminance, double *outRed, double *outGreen, double *outBlue)
+{
+  if (saturation < 1e-4)
+  {
+    *outRed = *outGreen = *outBlue = luminance;
+    return;
+  }
+
+  double v2 = (luminance < 0.5) ? (luminance * (1.0 + saturation)) : (luminance + saturation - saturation * luminance);
+  double v1 = 2.0 * luminance - v2;
+
+  *outRed   = hue2rgb(v1, v2, hue + 1.0 / 3.0);
+  *outGreen = hue2rgb(v1, v2, hue);
+  *outBlue  = hue2rgb(v1, v2, hue - 1.0 / 3.0);
+}
+
+EM_BOOL raf(double time, void *userData)
+{
+  WGpuCommandEncoder encoder = wgpu_device_create_command_encoder(device, 0);
+
+  WGpuRenderPassColorAttachment colorAttachment = {};
+  colorAttachment.view = wgpu_texture_create_view(wgpu_swap_chain_get_current_texture(swapChain), 0);
+
+  double hue = emscripten_math_fmod(time * 0.00005, 1.0);
+  hsl2rgb(hue, 1.0, 0.5, &colorAttachment.loadColor[0], &colorAttachment.loadColor[1], &colorAttachment.loadColor[2]);
+  colorAttachment.loadColor[3] = 0.05;
+
+  WGpuRenderPassDescriptor passDesc = {};
+  passDesc.numColorAttachments = 1;
+  passDesc.colorAttachments = &colorAttachment;
+
+  wgpu_render_pass_encoder_end_pass(wgpu_command_encoder_begin_render_pass(encoder, &passDesc));
+  wgpu_queue_submit_one_and_destroy(defaultQueue, wgpu_command_encoder_finish(encoder));
+
+  return EM_TRUE;
+}
+
+void ObtainedWebGpuDevice(WGpuDevice result, void *userData)
+{
+  device = result;
+  defaultQueue = wgpu_device_get_default_queue(device);
+
+  WGpuCanvasContext canvasContext = wgpu_canvas_get_canvas_context("canvas");
+
+  WGpuSwapChainDescriptor swapChainDesc = WGPU_SWAP_CHAIN_DESCRIPTOR_DEFAULT_INITIALIZER;
+  swapChainDesc.device = device;
+  swapChainDesc.format = wgpu_canvas_context_get_swap_chain_preferred_format(canvasContext, adapter);
+  swapChain = wgpu_canvascontext_configure_swap_chain(canvasContext, &swapChainDesc);
+
+  emscripten_request_animation_frame_loop(raf, 0);
+}
+
+void ObtainedWebGpuAdapter(WGpuAdapter result, void *userData)
+{
+  adapter = result;
+
+  WGpuDeviceDescriptor deviceDesc = WGPU_DEVICE_DESCRIPTOR_DEFAULT_INITIALIZER;
+  wgpu_adapter_request_device_async(adapter, &deviceDesc, ObtainedWebGpuDevice, 0);
+}
+
+int main(int argc, char **argv)
+{
+  WGpuRequestAdapterOptions options = {};
+  navigator_gpu_request_adapter_async(&options, ObtainedWebGpuAdapter, 0);
+}

hello_triangle/hello_triangle_minimal.c

@@ -39,10 +39,9 @@ void ObtainedWebGpuDevice(WGpuDevice result, void *userData)
 
   WGpuCanvasContext canvasContext = wgpu_canvas_get_canvas_context("canvas");
 
-  WGpuSwapChainDescriptor swapChainDesc = {};
+  WGpuSwapChainDescriptor swapChainDesc = WGPU_SWAP_CHAIN_DESCRIPTOR_DEFAULT_INITIALIZER;
   swapChainDesc.device = device;
   swapChainDesc.format = wgpu_canvas_context_get_swap_chain_preferred_format(canvasContext, adapter);
-  swapChainDesc.usage = WGPU_TEXTURE_USAGE_RENDER_ATTACHMENT;
 
   swapChain = wgpu_canvascontext_configure_swap_chain(canvasContext, &swapChainDesc);
 

hello_triangle/hello_triangle_verbose.c

@@ -69,11 +69,10 @@ void ObtainedWebGpuDevice(WGpuDevice result, void *userData)
   assert(canvasContext);
   assert(wgpu_is_canvas_context(canvasContext));
 
-  WGpuSwapChainDescriptor swapChainDesc = {};
+  WGpuSwapChainDescriptor swapChainDesc = WGPU_SWAP_CHAIN_DESCRIPTOR_DEFAULT_INITIALIZER;
   swapChainDesc.device = device;
   swapChainDesc.format = wgpu_canvas_context_get_swap_chain_preferred_format(canvasContext, adapter);
   printf("Preferred swap chain format: %s\n", wgpu_enum_to_string(swapChainDesc.format));
-  swapChainDesc.usage = WGPU_TEXTURE_USAGE_RENDER_ATTACHMENT;
 
   swapChain = wgpu_canvascontext_configure_swap_chain(canvasContext, &swapChainDesc);
   assert(wgpu_is_swap_chain(swapChain));

lib/lib_webgpu.cpp

@@ -10,6 +10,13 @@ const char *wgpu_enum_to_string(int enumValue)
   return (enumValue >= 0 && enumValue < sizeof(wgpuStrings)/sizeof(wgpuStrings[0])) ? wgpuStrings[enumValue] : "(invalid WebGPU enum)";
 }
 
+const WGpuDeviceDescriptor WGPU_DEVICE_DESCRIPTOR_DEFAULT_INITIALIZER = {
+};
+
+const WGpuSwapChainDescriptor WGPU_SWAP_CHAIN_DESCRIPTOR_DEFAULT_INITIALIZER = {
+  .usage = WGPU_TEXTURE_USAGE_RENDER_ATTACHMENT
+};
+
 const WGpuColorTargetState WGPU_COLOR_TARGET_STATE_DEFAULT_INITIALIZER = {
   .blend = (WGpuBlendState) {
     .color = (WGpuBlendComponent) {

lib/lib_webgpu.h

@@ -393,13 +393,15 @@ typedef struct WGpuDeviceDescriptor
   uint32_t maxVertexAttributes;
   uint32_t maxVertexBufferArrayStride;
 } WGpuDeviceDescriptor;
+extern const WGpuDeviceDescriptor WGPU_DEVICE_DESCRIPTOR_DEFAULT_INITIALIZER;
 
 typedef struct WGpuSwapChainDescriptor
 {
   WGpuDevice device;
   WGPU_TEXTURE_FORMAT format;
   WGPU_TEXTURE_USAGE_FLAGS usage;
 } WGpuSwapChainDescriptor;
+extern const WGpuSwapChainDescriptor WGPU_SWAP_CHAIN_DESCRIPTOR_DEFAULT_INITIALIZER;
 
 typedef struct WGpuShaderModuleDescriptor
 {
@@ -565,10 +567,12 @@ typedef struct WGpuRenderPassDescriptor
   WGpuQuerySet occlusionQuerySet;
 } WGpuRenderPassDescriptor;
 
+/*
 typedef struct WGpuSamplerDescriptor
 {
   // TODO https://gpuweb.github.io/gpuweb/#dictdef-gpusamplerdescriptor
 } WGpuSamplerDescriptor;
+*/
 
 const char *wgpu_enum_to_string(int enumValue);
 

lib/lib_webgpu.js

@@ -217,7 +217,7 @@ mergeInto(LibraryManager.library, {
         {{{ wdebugdir('adapter'); }}}
         wgpu[id] = adapter;
         adapter.wid = id;
-        dynCall('vii', adapterCallback, [id, userData]);
+        {{{ makeDynCall('vii', 'adapterCallback') }}}(id, userData);
       });
       return id;
     }
@@ -312,7 +312,7 @@ mergeInto(LibraryManager.library, {
       // Register an ID for the defaultQueue of this newly created device
       wgpuStore(device['defaultQueue']);
 
-      dynCall('vii', deviceCallback, [id, userData]);
+      {{{ makeDynCall('vii', 'deviceCallback') }}}(id, userData);
     });
   },
 

make.bat

@@ -1,5 +1,11 @@
 @mkdir out >NUL 2>&1
-@set ARGS=--js-library lib\lib_webgpu.js lib\lib_webgpu.cpp -Ilib -s MINIMAL_RUNTIME=2 -O3 -s ENVIRONMENT=web -s DYNCALLS=1 -s DEFAULT_LIBRARY_FUNCS_TO_INCLUDE=["$dynCall"] -s TEXTDECODER=2 -s SUPPORT_ERRNO=0
 
-call emcc hello_triangle\hello_triangle_verbose.c -o out\hello_triangle_verbose.html %ARGS% -g2 -s ASSERTIONS=1
-call emcc hello_triangle\hello_triangle_minimal.c -o out\hello_triangle_minimal.html %ARGS% -DNDEBUG --closure 1 --closure-args "--externs lib/webgpu_closure_externs.js"
+@set ARGS_DEBUG_DEEP=-O0 -g2 -s ASSERTIONS=1
+@set ARGS_DEBUG_OPTIMIZED=-DNDEBUG -O3 -g2 -s WASM=0
+@set ARGS_RELEASE=-DNDEBUG --closure 0 --closure-args "--externs lib/webgpu_closure_externs.js" -O3
+
+@set ARGS=--js-library lib\lib_webgpu.js lib\lib_webgpu.cpp -Ilib -s MINIMAL_RUNTIME=2 -s ENVIRONMENT=web -s TEXTDECODER=2 -s SUPPORT_ERRNO=0 --shell-file shell.html -s TOTAL_STACK=16KB -s INITIAL_MEMORY=128KB
+
+call emcc hello_triangle\hello_triangle_verbose.c -o out\hello_triangle_verbose.html %ARGS% %ARGS_DEBUG%
+call emcc hello_triangle\hello_triangle_minimal.c -o out\hello_triangle_minimal.html %ARGS% %ARGS_RELEASE%
+call emcc clear_screen\clear_screen.c -o out\clear_screen.html %ARGS% %ARGS_DEBUG_OPTIMIZED%

shell.html

@@ -0,0 +1,45 @@
+<!doctype html><html lang="en-us"><head><meta charset="utf-8"></head>
+<body style='margin:0'>
+<canvas style='display:block; margin:auto;'></canvas>
+<script>
+#if !MODULARIZE
+  var Module = {
+#if USE_PTHREADS
+    worker: '{{{ PTHREAD_WORKER_FILE }}}'
+#endif
+};
+#endif
+
+function resizeCanvas() {
+	var c = document.querySelector('canvas');
+	c.style.width = window.innerWidth + 'px';
+	c.style.height = window.innerHeight + 'px';
+	c.width = Math.round(window.innerWidth * window.devicePixelRatio);
+	c.height = Math.round(window.innerHeight * window.devicePixelRatio);
+}
+resizeCanvas();
+onresize = resizeCanvas;
+
+#if WASM == 2
+  var supportsWasm = window.WebAssembly && location.search.indexOf('_rwasm=0') < 0;
+#endif
+
+// Depending on the build flags that one uses, different files need to be downloaded
+// to load the compiled page. The right set of files will be expanded to be downloaded
+// via the directive below.
+{{{ DOWNLOAD_JS_AND_WASM_FILES }}}
+
+#if SINGLE_FILE
+// If we are doing a SINGLE_FILE=1 build, inlined JS runtime code follows here:
+{{{ JS_CONTENTS_IN_SINGLE_FILE_BUILD }}}
+
+#if MODULARIZE
+// Launch the MODULARIZEd build.
+{{{ EXPORT_NAME }}}({});
+#endif
+
+#endif
+
+</script>
+</body>
+</html>