1// tImageBMP.h 
2// 
3// This class knows how to load and save windows bitmap (.bmp) files into tPixel arrays. These tPixels may be 'stolen' by the 
4// tPicture's constructor if a targa file is specified. After the array is stolen the tImageBMP is invalid. This is 
5// purely for performance. 
6// 
7// The code in this module is a modification of code from https://github.com/phm97/bmp under the BSD 2-Clause License: 
8// 
9// Copyright (c) 2019, phm97 
10// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the 
11// following conditions are met: 
12// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following 
13// disclaimer. 
14// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the 
15// following disclaimer in the documentation and/or other materials provided with the distribution. 
16// 
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
18// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
19// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
20// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
21// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
22// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
23// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
24// 
25// The modifications to use Tacent datatypes and conversion to C++ are under the ISC licence: 
26// 
27// Copyright (c) 2020 Tristan Grimmer. 
28// Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby 
29// granted, provided that the above copyright notice and this permission notice appear in all copies. 
30// 
31// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL 
32// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, 
33// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 
34// AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 
35// PERFORMANCE OF THIS SOFTWARE. 
36 
37#pragma once 
38#include <Foundation/tString.h> 
39#include <Math/tColour.h> 
40#include <Image/tPixelFormat.h> 
41namespace tImage 
42{ 
43 
44 
45class tImageBMP 
46{ 
47public: 
48 // Creates an invalid tImageBMP. You must call Load manually. 
49 tImageBMP() { } 
50 tImageBMP(const tString& bmpFile) { Load(bmpFile); } 
51 
52 // This one sets from a supplied pixel array. If steal is true it takes ownership of the pixels pointer. Otherwise 
53 // it just copies the data out. 
54 tImageBMP(tPixel* pixels, int width, int height, bool steal = false) { Set(pixels, width, height, steal); } 
55 
56 virtual ~tImageBMP() { Clear(); } 
57 
58 // Clears the current tImageBMP before loading. Supports RGBA, RGB, R5G5B5A1, 8-bit indexed, 4-bit indexed, 1-bit 
59 // indexed, and run-length encoded RLE4 and RLE8. Returns success. If false returned, object is invalid. 
60 bool Load(const tString& bmpFile); 
61 
62 // This one sets from a supplied pixel array. If steal is true it takes ownership of the pixels pointer. Otherwise 
63 // it just copies the data out. 
64 bool Set(tPixel* pixels, int width, int height, bool steal = false); 
65 
66 enum class tFormat 
67 { 
68 Invalid, // Invalid must be 0. 
69 Auto, // Save function will decide format. Bit24 if all image pixels are opaque and Bit32 otherwise. 
70 BPP24, // RGB. 24 bit colour. 
71 BPP32 // RGBA. 24 bit colour and 8 bits opacity in the alpha channel. 
72 }; 
73 
74 // Saves the tImageBMP to the bmp file specified. The extension must be ".bmp". If tFormat is Auto, this function 
75 // will decide the format. BPP24 if all image pixels are opaque and BPP32 otherwise. Returns the format that the 
76 // file was saved in, or tFormat::Invalid if there was a problem. Since Invalid is 0, you can use an 'if'. 
77 tFormat Save(const tString& bmpFile, tFormat = tFormat::Auto) const; 
78 
79 // After this call no memory will be consumed by the object and it will be invalid. 
80 void Clear(); 
81 bool IsValid() const { return Pixels ? true : false; } 
82 
83 int GetWidth() const { return Width; } 
84 int GetHeight() const { return Height; } 
85 
86 // All pixels must be opaque (alpha = 1) for this to return true. 
87 bool IsOpaque() const; 
88 
89 // After this call you are the owner of the pixels and must eventually delete[] them. This tImageBMP object is 
90 // invalid afterwards. 
91 tPixel* StealPixels(); 
92 tPixel* GetPixels() const { return Pixels; } 
93 tPixelFormat SrcPixelFormat = tPixelFormat::Invalid; 
94 
95private: 
96 const uint16 FourCC = 0x4D42; 
97 
98 #pragma pack(push, r1, 1) 
99 struct Header 
100 { 
101 uint16 FourCC; 
102 int32 Size; 
103 int32 AppId; 
104 int32 Offset; 
105 }; 
106 
107 struct InfoHeader 
108 { 
109 int32 HeaderSize; 
110 int32 Width; 
111 int32 Height; 
112 int16 NumPlanes; 
113 int16 BPP; 
114 int32 Compression; 
115 int32 ImageSize; 
116 int32 HorizontalResolution; 
117 int32 VerticalResolution; 
118 int32 ColoursUsed; 
119 int32 ColoursImportant; 
120 }; 
121 
122 struct PaletteColour 
123 { 
124 uint8 B; 
125 uint8 G; 
126 uint8 R; 
127 uint8 A; 
128 }; 
129 #pragma pack(pop, r1) 
130 
131 void ReadRow_Pixels32 (tFileHandle, uint8* dest); 
132 void ReadRow_Pixels24 (tFileHandle, uint8* dest); 
133 void ReadRow_Pixels16 (tFileHandle, uint8* dest); 
134 void ReadRow_Indexed8 (tFileHandle, uint8* dest, PaletteColour* palette); 
135 void ReadRow_Indexed4 (tFileHandle, uint8* dest, PaletteColour* palette); 
136 void ReadRow_Indexed1 (tFileHandle, uint8* dest, PaletteColour* palette); 
137 void ReadRow_IndexedRLE8(tFileHandle, uint8* dest, PaletteColour* palette); 
138 void ReadRow_IndexedRLE4(tFileHandle, uint8* dest, PaletteColour* palette); 
139 
140 // So this is a neat C++11 feature. Allows simplified constructors. 
141 int Width = 0; 
142 int Height = 0; 
143 tPixel* Pixels = nullptr; 
144}; 
145 
146 
147// Implementation below this line. 
148 
149 
150inline void tImageBMP::Clear() 
151{ 
152 Width = 0; 
153 Height = 0; 
154 delete[] Pixels; 
155 Pixels = nullptr; 
156 SrcPixelFormat = tPixelFormat::Invalid; 
157} 
158 
159 
160} 
161