1// tImageEXR.h 
2// 
3// This knows how to load and save OpenEXR images (.exr). It knows the details of the exr high dynamic range 
4// file format and loads the data into a tPixel array. These tPixels may be 'stolen' by the tPicture's constructor if 
5// an EXR file is specified. After the array is stolen the tImageEXR is invalid. This is purely for performance. 
6// 
7// Copyright (c) 2020 Tristan Grimmer. 
8// Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby 
9// granted, provided that the above copyright notice and this permission notice appear in all copies. 
10// 
11// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL 
12// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, 
13// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 
14// AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 
15// PERFORMANCE OF THIS SOFTWARE. 
16 
17#pragma once 
18#include <Foundation/tString.h> 
19#include <Math/tColour.h> 
20#include <Image/tPixelFormat.h> 
21namespace tImage 
22{ 
23 
24 
25class tImageEXR 
26{ 
27public: 
28 // Gamma range [0.6, 3.0] 
29 inline const static float DefaultExposure = 1.0f; // [ -10.0, 10.0 ] 
30 inline const static float DefaultDefog = 0.0f; // [ 0.0, 0.1 ] Try to keep below 0.01. 
31 inline const static float DefaultKneeLow = 0.0f; // [ -3.0, 3.0 ] 
32 inline const static float DefaultKneeHigh = 3.5f; // [ 3.5, 7.5 ] 
33 
34 // Creates an invalid tImageEXR. You must call Load manually. 
35 tImageEXR() { } 
36 
37 // If something went wrong (like partNum not existing) image will be invalid. 
38 tImageEXR 
39 ( 
40 const tString& exrFile, 
41 int partNum = 0, 
42 float gamma = tMath::DefaultGamma, 
43 float exposure = DefaultExposure, 
44 float defog = DefaultDefog, 
45 float kneeLow = DefaultKneeLow, 
46 float kneeHigh = DefaultKneeHigh 
47 ) { Load(exrFile, partNum, gamma, exposure, defog, kneeLow, kneeHigh); } 
48 
49 // This one sets from a supplied pixel array. It just reads the data (or steals the array if steal set). 
50 tImageEXR(tPixel* pixels, int width, int height, bool steal = false) { Set(pixels, width, height, steal); } 
51 
52 virtual ~tImageEXR() { Clear(); } 
53 
54 // Clears the current tImageEXR before loading. If false returned object is invalid. 
55 bool Load 
56 ( 
57 const tString& exrFile, 
58 int partNum = 0, // Part num to load. 0-based. Returns false if didn't exist. 
59 float gamma = tMath::DefaultGamma, 
60 float exposure = DefaultExposure, 
61 float defog = DefaultDefog, 
62 float kneeLow = DefaultKneeLow, 
63 float kneeHigh = DefaultKneeHigh 
64 ); 
65 
66 // This one sets from a supplied pixel array. 
67 bool Set(tPixel* pixels, int width, int height, bool steal = false); 
68 
69 // Saves the tImageEXR to the exr file specified. The extension of filename must be "exr". Returns success. 
70 bool Save(const tString& exrFile) const; 
71 
72 // After this call no memory will be consumed by the object and it will be invalid. 
73 void Clear(); 
74 bool IsValid() const { return Pixels ? true : false; } 
75 
76 int GetWidth() const { return Width; } 
77 int GetHeight() const { return Height; } 
78 
79 // After this call you are the owner of the pixels and must eventually delete[] them. This tImageEXR object is 
80 // invalid afterwards. 
81 tPixel* StealPixels(); 
82 tPixel* GetPixels() const { return Pixels; } 
83 tPixelFormat SrcPixelFormat = tPixelFormat::Invalid; 
84 
85private: 
86 int Width = 0; 
87 int Height = 0; 
88 tPixel* Pixels = nullptr; 
89}; 
90 
91 
92// Implementation blow this line. 
93 
94 
95inline void tImageEXR::Clear() 
96{ 
97 Width = 0; 
98 Height = 0; 
99 delete[] Pixels; 
100 Pixels = nullptr; 
101 SrcPixelFormat = tPixelFormat::Invalid; 
102} 
103 
104 
105} 
106