1// tImageTGA.h 
2// 
3// This class knows how to load and save targa (.tga) 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 tImageTGA is invalid. This is 
5// purely for performance. 
6// 
7// Copyright (c) 2006, 2017, 2019, 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 tImageTGA 
26{ 
27public: 
28 // Creates an invalid tImageTGA. You must call Load manually. 
29 tImageTGA() { } 
30 tImageTGA(const tString& tgaFile) { Load(tgaFile); } 
31 
32 // The data is copied out of tgaFileInMemory. Go ahead and delete after if you want. 
33 tImageTGA(const uint8* tgaFileInMemory, int numBytes) { Set(tgaFileInMemory, numBytes); } 
34 
35 // This one sets from a supplied pixel array. If steal is true it takes ownership of the pixels pointer. Otherwise 
36 // it just copies the data out. 
37 tImageTGA(tPixel* pixels, int width, int height, bool steal = false) { Set(pixels, width, height, steal); } 
38 
39 virtual ~tImageTGA() { Clear(); } 
40 
41 // Clears the current tImageTGA before loading. 16, 24, or 32 bit targas can be loaded. The tga may be uncompressed 
42 // or RLE compressed. Other compression methods are rare and unsupported. Returns success. If false returned, 
43 // object is invalid. 
44 bool Load(const tString& tgaFile); 
45 bool Set(const uint8* tgaFileInMemory, int numBytes); 
46 
47 // This one sets from a supplied pixel array. If steal is true it takes ownership of the pixels pointer. Otherwise 
48 // it just copies the data out. 
49 bool Set(tPixel* pixels, int width, int height, bool steal = false); 
50 
51 enum class tFormat 
52 { 
53 Invalid, // Invalid must be 0. 
54 Auto, // Save function will decide format. Bit24 if all image pixels are opaque and Bit32 otherwise. 
55 Bit24, // 24 bit colour. 
56 Bit32 // 24 bit colour with 8 bits opacity in the alpha channel. 
57 }; 
58 enum class tCompression 
59 { 
60 None, // No compression. 
61 RLE // Run Length Encoding. 
62 }; 
63 
64 // Saves the tImageTGA to the Targa file specified. The extension of filename must be ".tga". If tFormat is Auto, 
65 // this function will decide the format. Bit24 if all image pixels are opaque and Bit32 otherwise. Returns the format 
66 // that the file was saved in, or tFormat::Invalid if there was a problem. Since Invalid is 0, you can use an 'if'. 
67 tFormat Save(const tString& tgaFile, tFormat = tFormat::Auto, tCompression = tCompression::RLE) const; 
68 
69 // After this call no memory will be consumed by the object and it will be invalid. 
70 void Clear(); 
71 bool IsValid() const { return Pixels ? true : false; } 
72 
73 int GetWidth() const { return Width; } 
74 int GetHeight() const { return Height; } 
75 
76 // All pixels must be opaque (alpha = 1) for this to return true. 
77 bool IsOpaque() const; 
78 
79 // After this call you are the owner of the pixels and must eventually delete[] them. This tImageTGA object is 
80 // invalid afterwards. 
81 tPixel* StealPixels(); 
82 tPixel* GetPixels() const { return Pixels; } 
83 tPixelFormat SrcPixelFormat = tPixelFormat::Invalid; 
84 
85private: 
86 bool SaveUncompressed(const tString& tgaFile, tFormat) const; 
87 bool SaveCompressed(const tString& tgaFile, tFormat) const; 
88 void ReadColourBytes(tColouri& dest, const uint8* src, int bitDepth); 
89 
90 // So this is a neat C++11 feature. Allows simplified constructors. 
91 int Width = 0; 
92 int Height = 0; 
93 tPixel* Pixels = nullptr; 
94}; 
95 
96 
97// Implementation below this line. 
98 
99 
100inline void tImageTGA::Clear() 
101{ 
102 Width = 0; 
103 Height = 0; 
104 delete[] Pixels; 
105 Pixels = nullptr; 
106 SrcPixelFormat = tPixelFormat::Invalid; 
107} 
108 
109 
110} 
111 
112 
113 
114