1 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "base/logging.h"
6 #include "base/memory/scoped_ptr.h"
7 
8 #include "main.h"
9 #include "testbase.h"
10 
11 
12 namespace glbench {
13 
14 
15 class ReadPixelTest : public TestBase {
16  public:
ReadPixelTest()17   ReadPixelTest() : pixels_(NULL) {}
~ReadPixelTest()18   virtual ~ReadPixelTest() {}
19   virtual bool TestFunc(uint64_t iterations);
20   virtual bool Run();
Name() const21   virtual const char* Name() const { return "pixel_read"; }
IsDrawTest() const22   virtual bool IsDrawTest() const { return false; }
Unit() const23   virtual const char* Unit() const { return "mpixels_sec"; }
24 
25  private:
26   void* pixels_;
27   DISALLOW_COPY_AND_ASSIGN(ReadPixelTest);
28 };
29 
30 
TestFunc(uint64_t iterations)31 bool ReadPixelTest::TestFunc(uint64_t iterations) {
32   glReadPixels(0, 0, g_width, g_height, GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
33   CHECK(glGetError() == 0);
34   for (uint64_t i = 0; i < iterations - 1; i++)
35     glReadPixels(0, 0, g_width, g_height, GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
36   return true;
37 }
38 
39 
Run()40 bool ReadPixelTest::Run() {
41   // One GL_RGBA pixel takes 4 bytes.
42   const int row_size = g_width * 4;
43   // Default GL_PACK_ALIGNMENT is 4, round up pixel row size to multiple of 4.
44   // This is a no-op because row_size is already divisible by 4.
45   // One is added so that we can test reads into unaligned location.
46   scoped_ptr<char[]> buf(new char[((row_size + 3) & ~3) * g_height + 1]);
47   pixels_ = buf.get();
48   RunTest(this, "pixel_read", g_width * g_height, g_width, g_height, true);
49 
50   // Reducing GL_PACK_ALIGNMENT can only make rows smaller.  No need to
51   // reallocate the buffer.
52   glPixelStorei(GL_PACK_ALIGNMENT, 1);
53   RunTest(this, "pixel_read_2", g_width * g_height, g_width, g_height, true);
54 
55   pixels_ = static_cast<void*>(buf.get() + 1);
56   RunTest(this, "pixel_read_3", g_width * g_height, g_width, g_height, true);
57 
58   return true;
59 }
60 
61 
GetReadPixelTest()62 TestBase* GetReadPixelTest() {
63   return new ReadPixelTest;
64 }
65 
66 
67 } // namespace glbench
68