Upgrade PixelStorei to ES3/WebGL2.

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <stdio.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 165 matching lines @@
 template <typename MANAGER_TYPE, typename OBJECT_TYPE>
 GLuint GetClientId(const MANAGER_TYPE* manager, const OBJECT_TYPE* object) {
   DCHECK(manager);
   GLuint client_id = 0;
   if (object) {
     manager->GetClientId(object->service_id(), &client_id);
   }
   return client_id;
 }
 
+template <typename OBJECT_TYPE>
+GLuint GetServiceId(const OBJECT_TYPE* object) {
+  return object ? object->service_id() : 0;
+}
+
 struct Vec4f {
   explicit Vec4f(const Vec4& data) {
     data.GetValues(v);
   }
 
   GLfloat v[4];
 };
 
 }  // namespace
 
@@ skipping 8599 matching lines @@
           GL_PIXEL_PACK_BUFFER_ARB, 0, pixels_size, GL_MAP_READ_BIT);
     } else {
       data = glMapBuffer(GL_PIXEL_PACK_BUFFER_ARB, GL_READ_ONLY);
     }
     if (!data) {
       LOCAL_SET_GL_ERROR(GL_OUT_OF_MEMORY, "glMapBuffer",
                          "Unable to map memory for readback.");
       return;
     }
     memcpy(pixels, data, pixels_size);
-    // GL_PIXEL_PACK_BUFFER_ARB is currently unused, so we don't
-    // have to restore the state.
     glUnmapBuffer(GL_PIXEL_PACK_BUFFER_ARB);
-    glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0);
+    glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB,
+                 GetServiceId(state_.bound_pixel_pack_buffer.get()));
     glDeleteBuffersARB(1, &buffer);
   }
 
   if (result != NULL) {
     *result = true;
   }
 
   GLenum read_format = GetBoundReadFrameBufferInternalFormat();
   uint32 channels_exist = GLES2Util::GetChannelsForFormat(read_format);
   if ((channels_exist & 0x0008) == 0 &&
@@ skipping 59 matching lines @@
   GLsizei height = c.height;
   GLenum format = c.format;
   GLenum type = c.type;
   GLboolean async = static_cast<GLboolean>(c.async);
   if (width < 0 || height < 0) {
     LOCAL_SET_GL_ERROR(GL_INVALID_VALUE, "glReadPixels", "dimensions < 0");
     return error::kNoError;
   }
   typedef cmds::ReadPixels::Result Result;
   uint32 pixels_size;
+  // TODO(zmo): Need to handle the case of reading into a PIXEL_PACK_BUFFER in
+  // ES3, including more pack parameters.

[piman, 2015/12/01 01:27:33]

For safety, because we're not doing range checking on the pixel pack buffer, I
think the right thing to do is to fail with INVALID_OPERATION if a pack buffer
is bound, until it's fully implemented.

[Zhenyao Mo, 2015/12/01 22:11:53]

Done.

   if (!GLES2Util::ComputeImageDataSizes(
       width, height, 1, format, type, state_.pack_alignment, &pixels_size,
       NULL, NULL)) {
     return error::kOutOfBounds;
   }
   void* pixels = GetSharedMemoryAs<void*>(
       c.pixels_shm_id, c.pixels_shm_offset, pixels_size);
   if (!pixels) {
     return error::kOutOfBounds;
   }
@@ skipping 167 matching lines @@
       memset(dst, 0, unpadded_row_size);
 
       // If the row is in range, copy it.
       if (ry >= 0 && ry < max_size.height() && read_width > 0) {
         glReadPixels(
             read_x, ry, read_width, 1, format, type, dst + dest_row_offset);
       }
       dst += padded_row_size;
     }
   } else {
-    if (async && features().use_async_readpixels) {
+    if (async && features().use_async_readpixels &&
+        !state_.bound_pixel_pack_buffer.get()) {
+      // To simply the state tracking, we don't go down the asyn path if

[piman, 2015/12/01 01:27:33]

nit: asyn->async

[Zhenyao Mo, 2015/12/01 22:11:53]

Done.

+      // a PIXEL_PACK_BUFFER is bound (in which case the client can
+      // implement something similar on their own - all necessary functions
+      // should be exposed).
       GLuint buffer = 0;
       glGenBuffersARB(1, &buffer);
       glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, buffer);
       // For ANGLE client version 2, GL_STREAM_READ is not available.
       const GLenum usage_hint = feature_info_->gl_version_info().is_angle ?
           GL_STATIC_DRAW : GL_STREAM_READ;
       glBufferData(GL_PIXEL_PACK_BUFFER_ARB, pixels_size, NULL, usage_hint);
       GLenum error = glGetError();
       if (error == GL_NO_ERROR) {
+        // No need to worry about ES3 pxiel pack parameters, because no
+        // PIXEL_PACK_BUFFER is bound, and all these settings haven't been
+        // sent to GL.
         glReadPixels(x, y, width, height, format, type, 0);
         pending_readpixel_fences_.push(linked_ptr<FenceCallback>(
             new FenceCallback()));
         WaitForReadPixels(base::Bind(&GLES2DecoderImpl::FinishReadPixels,
                                      base::AsWeakPtr(this), c, buffer));
         glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0);
         return error::kNoError;
       } else {
         // On error, unbind pack buffer and fall through to sync readpixels
         glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0);
@@ skipping 11 matching lines @@
   }
 
   return error::kNoError;
 }
 
 error::Error GLES2DecoderImpl::HandlePixelStorei(uint32 immediate_data_size,
                                                  const void* cmd_data) {
   const gles2::cmds::PixelStorei& c =
       *static_cast<const gles2::cmds::PixelStorei*>(cmd_data);
   GLenum pname = c.pname;
-  GLenum param = c.param;
+  GLint param = c.param;
   if (!validators_->pixel_store.IsValid(pname)) {
     LOCAL_SET_GL_ERROR_INVALID_ENUM("glPixelStorei", pname, "pname");
     return error::kNoError;
   }
   switch (pname) {
     case GL_PACK_ALIGNMENT:
     case GL_UNPACK_ALIGNMENT:
-        if (!validators_->pixel_store_alignment.IsValid(param)) {
-            LOCAL_SET_GL_ERROR(
-                GL_INVALID_VALUE, "glPixelStorei", "param GL_INVALID_VALUE");
-            return error::kNoError;
-        }
-        break;
+      if (!validators_->pixel_store_alignment.IsValid(param)) {
+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_VALUE, "glPixelStorei", "invalid param");
+        return error::kNoError;
+      }
+      break;
+    case GL_PACK_ROW_LENGTH:
+    case GL_PACK_SKIP_PIXELS:
+    case GL_PACK_SKIP_ROWS:
+    case GL_UNPACK_ROW_LENGTH:
+    case GL_UNPACK_IMAGE_HEIGHT:
+    case GL_UNPACK_SKIP_PIXELS:
+    case GL_UNPACK_SKIP_ROWS:
+    case GL_UNPACK_SKIP_IMAGES:
+      if (param < 0) {
+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_VALUE, "glPixelStorei", "invalid param");
+        return error::kNoError;
+      }
     default:
-        break;
+      break;
   }
-  glPixelStorei(pname, param);
+  // For pack and unpack parameters (except for alignment), we don't apply them
+  // if no buffer is bound at PIXEL_PACK or PIXEL_UNPACK. We will handle pack
+  // and unpack according to the user specified parameters on the client side.
+  switch (pname) {
+    case GL_PACK_ROW_LENGTH:
+    case GL_PACK_SKIP_PIXELS:
+    case GL_PACK_SKIP_ROWS:
+      if (state_.bound_pixel_pack_buffer.get())
+        glPixelStorei(pname, param);
+      break;
+    case GL_UNPACK_ROW_LENGTH:
+    case GL_UNPACK_IMAGE_HEIGHT:
+    case GL_UNPACK_SKIP_PIXELS:
+    case GL_UNPACK_SKIP_ROWS:
+    case GL_UNPACK_SKIP_IMAGES:
+      if (state_.bound_pixel_unpack_buffer.get())
+        glPixelStorei(pname, param);
+      break;
+    default:
+      glPixelStorei(pname, param);
+      break;
+  }
   switch (pname) {
     case GL_PACK_ALIGNMENT:
-        state_.pack_alignment = param;
-        break;
+      state_.pack_alignment = param;
+      break;
     case GL_PACK_REVERSE_ROW_ORDER_ANGLE:
-        state_.pack_reverse_row_order = (param != 0);
-        break;
+      state_.pack_reverse_row_order = (param != 0);
+      break;
+    case GL_PACK_ROW_LENGTH:
+      state_.pack_row_length = param;
+      break;
+    case GL_PACK_SKIP_PIXELS:
+      state_.pack_skip_pixels = param;
+      break;
+    case GL_PACK_SKIP_ROWS:
+      state_.pack_skip_rows = param;
+      break;
     case GL_UNPACK_ALIGNMENT:
-        state_.unpack_alignment = param;
-        break;
+      state_.unpack_alignment = param;
+      break;
+    case GL_UNPACK_ROW_LENGTH:
+      state_.unpack_row_length = param;
+      break;
+    case GL_UNPACK_IMAGE_HEIGHT:
+      state_.unpack_image_height = param;
+      break;
+    case GL_UNPACK_SKIP_PIXELS:
+      state_.unpack_skip_pixels = param;
+      break;
+    case GL_UNPACK_SKIP_ROWS:
+      state_.unpack_skip_rows = param;
+      break;
+    case GL_UNPACK_SKIP_IMAGES:
+      state_.unpack_skip_images = param;
+      break;
     default:
-        // Validation should have prevented us from getting here.
-        NOTREACHED();
-        break;
+      // Validation should have prevented us from getting here.
+      NOTREACHED();
+      break;
   }
   return error::kNoError;
 }
 
 error::Error GLES2DecoderImpl::HandlePostSubBufferCHROMIUM(
     uint32 immediate_data_size,
     const void* cmd_data) {
   const gles2::cmds::PostSubBufferCHROMIUM& c =
       *static_cast<const gles2::cmds::PostSubBufferCHROMIUM*>(cmd_data);
   TRACE_EVENT0("gpu", "GLES2DecoderImpl::HandlePostSubBufferCHROMIUM");
@@ skipping 6164 matching lines @@
   return error::kNoError;
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu