1 files changed, 126 insertions, 0 deletions
diff --git a/dom/canvas/WebGLExtensionTextureFloat.cpp b/dom/canvas/WebGLExtensionTextureFloat.cpp
new file mode 100644
index 0000000000..d019515b23
--- /dev/null
+++ b/dom/canvas/WebGLExtensionTextureFloat.cpp
@@ -0,0 +1,126 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "WebGLExtensions.h"
+
+#include "GLContext.h"
+#include "mozilla/dom/WebGLRenderingContextBinding.h"
+#include "WebGLContext.h"
+#include "WebGLFormats.h"
+
+namespace mozilla {
+
+WebGLExtensionTextureFloat::WebGLExtensionTextureFloat(WebGLContext* webgl)
+    : WebGLExtensionBase(webgl) {
+  MOZ_ASSERT(IsSupported(webgl));
+
+  auto& fua = webgl->mFormatUsage;
+  gl::GLContext* gl = webgl->GL();
+
+  webgl::PackingInfo pi;
+  webgl::DriverUnpackInfo dui;
+  const GLint* swizzle = nullptr;
+
+  const auto fnAdd = [&](webgl::EffectiveFormat effFormat) {
+    MOZ_ASSERT_IF(swizzle, gl->IsSupported(gl::GLFeature::texture_swizzle));
+
+    auto usage = fua->EditUsage(effFormat);
+    usage->textureSwizzleRGBA = swizzle;
+    fua->AddTexUnpack(usage, pi, dui);
+
+    fua->AllowUnsizedTexFormat(pi, usage);
+  };
+
+  bool useSizedFormats = true;
+  const bool hasSizedLegacyFormats = gl->IsCompatibilityProfile();
+  if (gl->IsGLES() && gl->Version() < 300) {
+    useSizedFormats = false;
+  }
+
+  ////////////////
+
+  pi = {LOCAL_GL_RGBA, LOCAL_GL_FLOAT};
+  dui = {pi.format, pi.format, pi.type};
+  swizzle = nullptr;
+  if (useSizedFormats || gl->IsExtensionSupported(
+                             gl::GLContext::CHROMIUM_color_buffer_float_rgba)) {
+    // ANGLE only exposes renderable RGBA32F via
+    // CHROMIUM_color_buffer_float_rgba, which uses sized formats.
+    dui.internalFormat = LOCAL_GL_RGBA32F;
+  }
+  fnAdd(webgl::EffectiveFormat::RGBA32F);
+
+  //////
+
+  pi = {LOCAL_GL_RGB, LOCAL_GL_FLOAT};
+  dui = {pi.format, pi.format, pi.type};
+  swizzle = nullptr;
+  if (useSizedFormats) {
+    dui.internalFormat = LOCAL_GL_RGB32F;
+  }
+  fnAdd(webgl::EffectiveFormat::RGB32F);
+
+  //////
+
+  pi = {LOCAL_GL_LUMINANCE, LOCAL_GL_FLOAT};
+  dui = {pi.format, pi.format, pi.type};
+  swizzle = nullptr;
+  if (useSizedFormats) {
+    if (hasSizedLegacyFormats) {
+      dui.internalFormat = LOCAL_GL_LUMINANCE32F_ARB;
+    } else {
+      dui.internalFormat = LOCAL_GL_R32F;
+      dui.unpackFormat = LOCAL_GL_RED;
+      swizzle = webgl::FormatUsageInfo::kLuminanceSwizzleRGBA;
+    }
+  }
+  fnAdd(webgl::EffectiveFormat::Luminance32F);
+
+  //////
+
+  pi = {LOCAL_GL_ALPHA, LOCAL_GL_FLOAT};
+  dui = {pi.format, pi.format, pi.type};
+  swizzle = nullptr;
+  if (useSizedFormats) {
+    if (hasSizedLegacyFormats) {
+      dui.internalFormat = LOCAL_GL_ALPHA32F_ARB;
+    } else {
+      dui.internalFormat = LOCAL_GL_R32F;
+      dui.unpackFormat = LOCAL_GL_RED;
+      swizzle = webgl::FormatUsageInfo::kAlphaSwizzleRGBA;
+    }
+  }
+  fnAdd(webgl::EffectiveFormat::Alpha32F);
+
+  //////
+
+  pi = {LOCAL_GL_LUMINANCE_ALPHA, LOCAL_GL_FLOAT};
+  dui = {pi.format, pi.format, pi.type};
+  swizzle = nullptr;
+  if (useSizedFormats) {
+    if (hasSizedLegacyFormats) {
+      dui.internalFormat = LOCAL_GL_LUMINANCE_ALPHA32F_ARB;
+    } else {
+      dui.internalFormat = LOCAL_GL_RG32F;
+      dui.unpackFormat = LOCAL_GL_RG;
+      swizzle = webgl::FormatUsageInfo::kLumAlphaSwizzleRGBA;
+    }
+  }
+  fnAdd(webgl::EffectiveFormat::Luminance32FAlpha32F);
+}
+
+bool WebGLExtensionTextureFloat::IsSupported(const WebGLContext* webgl) {
+  if (webgl->IsWebGL2()) return false;
+
+  gl::GLContext* gl = webgl->GL();
+  if (!gl->IsSupported(gl::GLFeature::texture_float)) return false;
+
+  const bool needsSwizzle = gl->IsCoreProfile();
+  const bool hasSwizzle = gl->IsSupported(gl::GLFeature::texture_swizzle);
+  if (needsSwizzle && !hasSwizzle) return false;
+
+  return true;
+}
+
+}  // namespace mozilla