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 <memory>
6
7 #include "main.h"
8 #include "testbase.h"
9 #include "utils.h"
10
11 namespace glbench {
12
13 class ReadPixelTest : public TestBase {
14 public:
ReadPixelTest()15 ReadPixelTest() : pixels_(NULL) {}
~ReadPixelTest()16 virtual ~ReadPixelTest() {}
17 virtual bool TestFunc(uint64_t iterations);
18 virtual bool Run();
Name() const19 virtual const char* Name() const { return "pixel_read"; }
IsDrawTest() const20 virtual bool IsDrawTest() const { return false; }
Unit() const21 virtual const char* Unit() const { return "mpixels_sec"; }
22
23 private:
24 void* pixels_;
25 DISALLOW_COPY_AND_ASSIGN(ReadPixelTest);
26 };
27
TestFunc(uint64_t iterations)28 bool ReadPixelTest::TestFunc(uint64_t iterations) {
29 glReadPixels(0, 0, g_width, g_height, GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
30 CHECK(glGetError() == 0);
31 for (uint64_t i = 0; i < iterations - 1; i++)
32 glReadPixels(0, 0, g_width, g_height, GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
33 return true;
34 }
35
Run()36 bool ReadPixelTest::Run() {
37 // One GL_RGBA pixel takes 4 bytes.
38 const int row_size = g_width * 4;
39 // Default GL_PACK_ALIGNMENT is 4, round up pixel row size to multiple of 4.
40 // This is a no-op because row_size is already divisible by 4.
41 // One is added so that we can test reads into unaligned location.
42 std::unique_ptr<char[]> buf(new char[((row_size + 3) & ~3) * g_height + 1]);
43 pixels_ = buf.get();
44 RunTest(this, "pixel_read", g_width * g_height, g_width, g_height, true);
45
46 // Reducing GL_PACK_ALIGNMENT can only make rows smaller. No need to
47 // reallocate the buffer.
48 glPixelStorei(GL_PACK_ALIGNMENT, 1);
49 RunTest(this, "pixel_read_2", g_width * g_height, g_width, g_height, true);
50
51 pixels_ = static_cast<void*>(buf.get() + 1);
52 RunTest(this, "pixel_read_3", g_width * g_height, g_width, g_height, true);
53
54 return true;
55 }
56
GetReadPixelTest()57 TestBase* GetReadPixelTest() {
58 return new ReadPixelTest;
59 }
60
61 } // namespace glbench
62