File size: 7,342 Bytes
0c51b93
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
// This code contains NVIDIA Confidential Information and is disclosed to you
// under a form of NVIDIA software license agreement provided separately to you.
//
// Notice
// NVIDIA Corporation and its licensors retain all intellectual property and
// proprietary rights in and to this software and related documentation and
// any modifications thereto. Any use, reproduction, disclosure, or
// distribution of this software and related documentation without an express
// license agreement from NVIDIA Corporation is strictly prohibited.
//
// ALL NVIDIA DESIGN SPECIFICATIONS, CODE ARE PROVIDED "AS IS.". NVIDIA MAKES
// NO WARRANTIES, EXPRESSED, IMPLIED, STATUTORY, OR OTHERWISE WITH RESPECT TO
// THE MATERIALS, AND EXPRESSLY DISCLAIMS ALL IMPLIED WARRANTIES OF NONINFRINGEMENT,
// MERCHANTABILITY, AND FITNESS FOR A PARTICULAR PURPOSE.
//
// Information and code furnished is believed to be accurate and reliable.
// However, NVIDIA Corporation assumes no responsibility for the consequences of use of such
// information or for any infringement of patents or other rights of third parties that may
// result from its use. No license is granted by implication or otherwise under any patent
// or patent rights of NVIDIA Corporation. Details are subject to change without notice.
// This code supersedes and replaces all information previously supplied.
// NVIDIA Corporation products are not authorized for use as critical
// components in life support devices or systems without express written approval of
// NVIDIA Corporation.
//
// Copyright (c) 2013-2016 NVIDIA Corporation. All rights reserved.

#include "tga.h"
#include "core.h"
#include "types.h"

#include <stdio.h>
#include <string.h>

using namespace std;

struct TgaHeader
{
    uint8_t  identsize;          // size of ID field that follows 18 uint8_t header (0 usually)
    uint8_t  colourmaptype;      // type of colour map 0=none, 1=has palette
    uint8_t  imagetype;          // type of image 0=none,1=indexed,2=rgb,3=grey,+8=rle packed

    uint16_t colourmapstart;     // first colour map entry in palette
    uint16_t colourmaplength;    // number of colours in palette
    uint8_t  colourmapbits;      // number of bits per palette entry 15,16,24,32

    uint16_t xstart;             // image x origin
    uint16_t ystart;             // image y origin
    uint16_t width;              // image width in pixels
	uint16_t height;             // image height in pixels
    uint8_t  bits;               // image bits per pixel 8,16,24,32
    uint8_t  descriptor;         // image descriptor bits (vh flip bits)
    
    // pixel data follows header  
};

namespace
{

	void memwrite(void* src, uint32_t size, unsigned char*& buffer)
	{
		memcpy(buffer, src, size);
		buffer += size;
	}
}



bool TgaSave(const char* filename, const TgaImage& image, bool rle)
{
	FILE* f = fopen(filename, "wb");
	if (f)
	{
		bool b = TgaSave(f, image, rle);
		fclose(f);

		return b;
	}

	return false;
}

bool TgaSave(FILE* f, const TgaImage& image, bool rle)
{
	TgaHeader header;

	header.identsize = 0;
	header.colourmaptype = 0;
	header.imagetype = rle?9:2;
	header.colourmapstart = 0;
	header.colourmaplength = 0;
	header.colourmapbits = 0;
	header.xstart = 0;
	header.ystart = 0;
	header.width = image.m_width;
	header.height = image.m_height;
	header.bits = 32;
	header.descriptor = 0;//uint16((1<<3)|(1<<5));

	if (f)
	{
		unsigned char* data = (unsigned char*)new uint32_t[image.m_width*image.m_height + sizeof(header)];
		unsigned char* writeptr = data;
				
		memwrite(&header.identsize, sizeof(header.identsize), writeptr);
		memwrite(&header.colourmaptype, sizeof(header.colourmaptype), writeptr);
		memwrite(&header.imagetype, sizeof(header.imagetype), writeptr);
		memwrite(&header.colourmapstart, sizeof(header.colourmapstart), writeptr);
		memwrite(&header.colourmaplength, sizeof(header.colourmaplength), writeptr);
		memwrite(&header.colourmapbits, sizeof(header.colourmapbits), writeptr);
		memwrite(&header.xstart, sizeof(header.xstart), writeptr);
		memwrite(&header.ystart, sizeof(header.ystart), writeptr);
		memwrite(&header.width, sizeof(header.width), writeptr);
		memwrite(&header.height, sizeof(header.height), writeptr);
		memwrite(&header.bits, sizeof(header.bits), writeptr);
		memwrite(&header.descriptor, sizeof(header.descriptor), writeptr);

		union texel
		{
			uint32_t u32;
			uint8_t u8[4];
		};
		
		texel* t = (texel*)image.m_data;
		for (int i=0; i < image.m_width*image.m_height; ++i)
		{
			texel tmp = t[i];
			swap(tmp.u8[0], tmp.u8[2]);
			memwrite(&tmp.u32, 4, writeptr);
		}
			 
		fwrite(data, writeptr-data, 1, f);
		//fclose(f); 

		delete[] data;

		return true;
	}	
	else
	{
		return false;
	}
}


bool TgaLoad(const char* filename, TgaImage& image)
{
	if (!filename)
		return false;

	FILE* aTGAFile = fopen(filename, "rb");
	if (aTGAFile == NULL)
	{
		printf("Texture: could not open %s for reading.\n", filename);
		return NULL;
	}

	char aHeaderIDLen;
	size_t err;
	err = fread(&aHeaderIDLen, sizeof(uint8_t), 1, aTGAFile);

	char aColorMapType;
	err = fread(&aColorMapType, sizeof(uint8_t), 1, aTGAFile);
	
	char anImageType;
	err = fread(&anImageType, sizeof(uint8_t), 1, aTGAFile);

	short aFirstEntryIdx;
	err = fread(&aFirstEntryIdx, sizeof(uint16_t), 1, aTGAFile);

	short aColorMapLen;
	err = fread(&aColorMapLen, sizeof(uint16_t), 1, aTGAFile);

	char aColorMapEntrySize;
	err = fread(&aColorMapEntrySize, sizeof(uint8_t), 1, aTGAFile);	

	short anXOrigin;
	err = fread(&anXOrigin, sizeof(uint16_t), 1, aTGAFile);

	short aYOrigin;
	err = fread(&aYOrigin, sizeof(uint16_t), 1, aTGAFile);

	short anImageWidth;
	err = fread(&anImageWidth, sizeof(uint16_t), 1, aTGAFile);	

	short anImageHeight;
	err = fread(&anImageHeight, sizeof(uint16_t), 1, aTGAFile);	

	char aBitCount = 32;
	err = fread(&aBitCount, sizeof(uint8_t), 1, aTGAFile);	

	char anImageDescriptor;// = 8 | (1<<5);
	err = fread((char*)&anImageDescriptor, sizeof(uint8_t), 1, aTGAFile);
	
	// supress warning
	(void)err;

	// total is the number of bytes we'll have to read
	uint8_t numComponents = aBitCount / 8;
	uint32_t numTexels = anImageWidth * anImageHeight;

	// allocate memory for image pixels
	image.m_width = anImageWidth;
	image.m_height = anImageHeight;
	image.m_data = new uint32_t[numTexels];

	// load the image pixels
	for (uint32_t i=0; i < numTexels; ++i)
	{
		union texel
		{
			uint32_t u32;
			uint8_t u8[4];
		};

		texel t;
		t.u32 = 0;

		if (!fread(&t.u32, numComponents, 1, aTGAFile))
		{
			printf("Texture: file not fully read, may be corrupt (%s)\n", filename);
		}

		// stores it as BGR(A) so we'll have to swap R and B.
		swap(t.u8[0], t.u8[2]);


		image.m_data[i] = t.u32;
	}

	// if bit 5 of the descriptor is set then the image is flipped vertically so we fix it up
	if (anImageDescriptor & (1 << 5))
	{

		// swap all the rows
		int rowSize = image.m_width*4;	

		uint8_t* buf = new uint8_t[image.m_width*4];
		uint8_t* start = (uint8_t*)image.m_data;
		uint8_t* end = &((uint8_t*)image.m_data)[rowSize*(image.m_height-1)];
		
		while (start < end)
		{
			memcpy(buf, end, rowSize);
			memcpy(end, start, rowSize);
			memcpy(start, buf, rowSize);

			start += rowSize;
			end -= rowSize;
		}

		delete[] buf;
	}

	fclose(aTGAFile);
	
	return true;
}

void TgaFree(const TgaImage& image)
{
	delete[] image.m_data;
}