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cnlohr/example_generate_texture.c

Last active April 12, 2023 10:09
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How to write 2D and 3D Unity Texture files from C
Raw
example_generate_texture.c
// Execute this with `tcc testgen.c -run`
#include <stdio.h>
#include "unityassettexture.h"
#include <math.h>
int main()
{
float asset3d[50][50][50][4] = {0};
int x, y, z;
for( z = 0; z < 50; z++ )
for( y = 0; y < 50; y++ )
for( x = 0; x < 50; x++ )
{
float lx = (x - 25.)/25. + sin(z*.1)*.5;
float ly = (y - 25.)/25. + cos(z*.1)*.5;
float lz = cos(z*.1);
float col = 1.-sqrt(lx*lx+ly*ly+lz*lz);
asset3d[z][y][x][0] = col-10;
asset3d[z][y][x][1] = col;
asset3d[z][y][x][2] = col-20;
asset3d[z][y][x][3] = 255;
}
WriteUnityImageAsset( "test3d.asset", asset3d, sizeof(asset3d), 50, 50, 50, UTE_RGBA_FLOAT | UTE_FLAG_IS_3D );
float asset2d[20][20][4] = {0};
for( y = 0; y < 20; y++ )
for( x = 0; x < 20; x++ )
{
asset2d[y][x][0] = fmod( x+y*9, 1.555 );;
asset2d[y][x][1] = fmod( x+y*9, 1.455 );;
asset2d[y][x][2] = fmod( x+y*9, 1.355 );;
asset2d[y][x][3] = 255;
}
WriteUnityImageAsset( "test2d.asset", asset2d, sizeof(asset2d), 20, 20, 0, UTE_RGBA_FLOAT );
}
Raw
unitytextruewriter.h
/**
C Utility for writing out 2D or 3D Unity Texture Assets.
https://gist.github.com/cnlohr/c88980e560ecb403cae6c6525b05ab2f
2021 <>< Charles Lohr - this code may be distributed under any of he following
licenses: CC0, MIT/x11, NewBSD licenses. Portions may be copied freely to the
extent allowable by law, no attribution required.
Example usage:
// Execute this with `tcc testgen.c -run`
#include <stdio.h>
#include "unityassettexture.h"
#include <math.h>
int main()
{
float asset3d[50][50][50][4] = {0};
int x, y, z;
for( z = 0; z < 50; z++ )
for( y = 0; y < 50; y++ )
for( x = 0; x < 50; x++ )
{
float lx = (x - 25.)/25. + sin(z*.1)*.5;
float ly = (y - 25.)/25. + cos(z*.1)*.5;
float lz = cos(z*.1);
float col = 1.-sqrt(lx*lx+ly*ly+lz*lz);
asset3d[z][y][x][0] = col-10;
asset3d[z][y][x][1] = col;
asset3d[z][y][x][2] = col-20;
asset3d[z][y][x][3] = 255;
}
WriteUnityImageAsset( "test3d.asset", asset3d, sizeof(asset3d), 50, 50, 50, UTE_RGBA_FLOAT | UTE_FLAG_IS_3D );
float asset2d[20][20][4] = {0};
for( y = 0; y < 20; y++ )
for( x = 0; x < 20; x++ )
{
asset2d[y][x][0] = fmod( x+y*9, 1.555 );;
asset2d[y][x][1] = fmod( x+y*9, 1.455 );;
asset2d[y][x][2] = fmod( x+y*9, 1.355 );;
asset2d[y][x][3] = 255;
}
WriteUnityImageAsset( "test2d.asset", asset2d, sizeof(asset2d), 20, 20, 0, UTE_RGBA_FLOAT );
}
*/
#ifndef _UNITYTEXTUREWRITER_H
#define _UNITYTEXTUREWRITER_H
#include <stdint.h>
// See https://github.com/Unity-Technologies/UnityCsReference/blob/master/Runtime/Export/Graphics/GraphicsEnums.cs
#define UTE_UNSPPORTED 0
#define UTE_ALPHA8 1
#define UTE_ARGB 2 // Or BGRA4 UNORM (16 bpp)
#define UTE_RGB24 3
#define UTE_RGBA32 4
#define UTE_ARGB32 5
#define UTE_ARGB_FLOAT 6
#define UTE_RGB16 7 // R5G6B5
#define UTE_BGR24 8
#define UTE_R16 9
#define UTE_RGBDXT1 10
#define UTE_RGBADXT3 11
#define UTE_RGBADXT5 12
#define UTE_RGBA16 13 // Really RGBA4444
#define UTE_BGRA32 14
#define UTE_R_HALF 15
#define UTE_RG_HALF 16
#define UTE_RGBA_HALF 17
#define UTE_R_FLOAT 18
#define UTE_RG_FLOAT 19
#define UTE_RGBA_FLOAT 20
#define UTE_YUYV 21
#define UTE_RGB9e5_SHARED_EXPONENT 22
#define UTE_RGB_FLOAT 23
#define UTE_RGB_HDR_BC6H 24
#define UTE_RGBA_BC7 25
#define UTE_R_BC4 26
#define UTE_RG_BC5 27
#define UTE_DXT1_UNORM 28
#define UTE_DXT5_UNORM 29
#define UTE_RGB_PVRTC_2BPP_UNORM 30
#define UTE_RGBA_PVRTC_2BPP_UNORM 31
#define UTE_RGB_PVRTC_4BPP_UNORM 32
#define UTE_RGBA_PVRTC_4BPP_UNORM 33
#define UTE_RGB_ETC_UNORM 34
#define UTE_R_EAC_UNORM 41
#define UTE_R_EAC_SNORM 42
#define UTE_RG_EAC_UNORM 43
#define UTE_RG_EAC_SNORM 44
#define UTE_RGB_ETC2_UNORM 45
#define UTE_RGBA_ETC2_PUNCHTHROUGH_UNORM 46
#define UTE_RGBA_ETC2_UNORM 47
#define UTE_RGBA_ATSC4X4_UNORM 48
#define UTE_RGBA_ATSC5x5_UNORM 49
#define UTE_RGBA_ATSC6x6_UNORM 50
#define UTE_RGBA_ATSC8x8_UNORM 51
#define UTE_RGBA_ATSC10x10_UNORM 52
#define UTE_RGBA_ATSC12x12_UNORM 53
#define UTE_RGBA_ATSC4x4B_UNORM 54
#define UTE_RGBA_ATSC5x5B_UNORM 55
#define UTE_RGBA_ATSC6x6B_UNORM 56
#define UTE_RGBA_ATSC8x8B_UNORM 57
#define UTE_RGBA_ATSC10x10B_UNORM 58
#define UTE_RGBA_ATSC12x12B_UNORM 59
#define UTE_RGB_ETCB_UNORM 60
#define UTE_RGBA_ETC2B_UNORM 61
#define UTE_RG8_UNORM 62
#define UTE_R8_UNORM 63
#define UTE_RGB_ETC_B_UNORM 64
// Note: For these formats, your object size must be correct. These are raw 16-bit formats.
#define UTE_RG32_UNORM 72
#define UTE_RGB48_UNORM 73
#define UTE_RGBA64_UNORM 74
#define UTE_FLAG_FORMAT_MASK 0xff
#define UTE_FLAG_ALPHA_IS_TRANSPARENCY 0x100
#define UTE_FLAG_FILTER_MODE_LINEAR 0x200
#define UTE_FLAG_FILTER_MODE_CLAMP_U 0x1000
#define UTE_FLAG_FILTER_MODE_CLAMP_V 0x2000
#define UTE_FLAG_FILTER_MODE_CLAMP_W 0x4000
#define UTE_FLAG_IS_3D 0x10000
static inline void WriteUnityImageAsset( const char * filename, void * data, int bytes, int width, int height, int depth, uint32_t flags )
{
FILE * f = fopen( filename, "w" );
fprintf( f, "%%YAML 1.1\n\
%%TAG !u! tag:unity3d.com,2011:\n\
--- %s\n\
Texture%dD:\n\
m_ObjectHideFlags: 0\n\
m_CorrespondingSourceObject: {fileID: 0}\n\
serializedVersion: 2\n\
m_Width: %d\n\
m_Height: %d\n\
m_Depth: %d\n\
m_CompleteImageSize: %d\n\
%s: %d\n\
m_MipCount: 1\n\
m_IsReadable: 1\n\
m_AlphaIsTransparency: %d\n\
m_ImageCount: 1\n\
m_TextureDimension: %d\n\
m_TextureSettings:\n\
serializedVersion: 2\n\
m_FilterMode: %d\n\
m_Aniso: 0\n\
m_MipBias: 0\n\
m_WrapU: %d\n\
m_WrapV: %d\n\
m_WrapW: %d\n\
m_LightmapFormat: 0\n\
m_ColorSpace: 0\n\
image data: %d\n\
_typelessdata: ",
(flags&UTE_FLAG_IS_3D)?"!u!117 &11700000":"!u!28 &2800000",
(flags&UTE_FLAG_IS_3D)?3:2, width, height, (flags&UTE_FLAG_IS_3D)?depth:1, bytes,
(flags&UTE_FLAG_IS_3D)?"m_Format":"m_TextureFormat",
flags & UTE_FLAG_FORMAT_MASK, !!(flags&UTE_FLAG_ALPHA_IS_TRANSPARENCY),
(flags&UTE_FLAG_IS_3D)?3:2, (flags&UTE_FLAG_FILTER_MODE_LINEAR)?1:0,
!!(flags & UTE_FLAG_FILTER_MODE_CLAMP_U),
!!(flags & UTE_FLAG_FILTER_MODE_CLAMP_V),
!!(flags & UTE_FLAG_FILTER_MODE_CLAMP_W),
bytes );
int i;
for( i = 0; i < bytes; i++ )
{
int value = ((uint8_t*)data)[i];
fprintf( f, "%02x", value );
}
fprintf( f, "\n m_StreamData:\n\
offset: 0\n\
size: 0\n\
path: \n" );
fclose( f );
}
#endif
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