10 Texture2D::Texture2D()
16 Uploads an image into the texture. Direct wrapper for glTexImage2D.
18 void Texture2D::image(int level, int ifmt, sizei width, sizei height, int border, GLenum fmt, GLenum type, void *data)
20 if(bound!=this) bind();
21 glTexImage2D(target, level, ifmt, width, height, border, fmt, type, data);
25 Uploads an image into the texture.
27 void Texture2D::image(int level, sizei width, sizei height, TextureFormat tfmt, void *data)
35 case LUMINANCE8: ifmt=GL_LUMINANCE; fmt=GL_LUMINANCE; type=GL_UNSIGNED_BYTE; break;
36 case LUMINANCE8_ALPHA8: ifmt=GL_LUMINANCE_ALPHA; fmt=GL_LUMINANCE_ALPHA; type=GL_UNSIGNED_BYTE; break;
37 case RGB8: ifmt=GL_RGB; fmt=GL_RGB; type=GL_UNSIGNED_BYTE; break;
38 case RGBA8: ifmt=GL_RGBA; fmt=GL_RGBA; type=GL_UNSIGNED_INT_8_8_8_8; break;
39 case BGR8: ifmt=GL_RGB; fmt=GL_BGR; type=GL_UNSIGNED_BYTE; break;
40 case BGRA8: ifmt=GL_RGBA; fmt=GL_BGRA; type=GL_UNSIGNED_INT_8_8_8_8; break;
44 image(level, ifmt, width, height, 0, fmt, type, data);
48 Loads an image from a file and uploads it into the texture. Currently assumes
49 the file to be a PNG image.
51 void Texture2D::image(const string &fn)
53 FILE *file=fopen(fn.c_str(), "r");
54 if(!file) throw Exception("Couldn't open "+fn);
57 fread(sig, 8, 1, file);
58 if(png_sig_cmp((png_byte *)sig, 0, 8))
59 throw Exception("Not a PNG image");
61 png_struct *pngs=png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
62 png_info *pngi=png_create_info_struct(pngs);
64 if(setjmp(png_jmpbuf(pngs)))
66 png_destroy_read_struct(&pngs, &pngi, 0);
68 throw Exception("PNG error");
70 png_init_io(pngs, file);
71 png_set_sig_bytes(pngs, 8);
73 png_read_info(pngs, pngi);
75 unsigned width=png_get_image_width(pngs, pngi);
76 unsigned height=png_get_image_height(pngs, pngi);
77 unsigned depth=png_get_bit_depth(pngs, pngi);
78 unsigned ctype=png_get_color_type(pngs, pngi);
80 if(ctype==PNG_COLOR_TYPE_PALETTE || depth<8)
82 png_destroy_read_struct(&pngs, &pngi, 0);
84 throw Exception("Invalid color type or bit depth");
88 png_set_strip_16(pngs);
95 case PNG_COLOR_TYPE_GRAY: fmt=LUMINANCE8; planes=1; break;
96 case PNG_COLOR_TYPE_GRAY_ALPHA: fmt=LUMINANCE8_ALPHA8; planes=2; break;
97 case PNG_COLOR_TYPE_RGB: fmt=RGB8; planes=3; break;
98 case PNG_COLOR_TYPE_RGB_ALPHA: fmt=RGBA8; planes=4; break;
101 png_byte *data=(png_byte *)malloc(width*height*planes);
102 png_byte *row_ptrs[height];
103 for(unsigned i=0; i<height; ++i)
104 row_ptrs[i]=data+(height-1-i)*width*planes;
106 png_read_image(pngs, row_ptrs);
108 image(0, width, height, fmt, data);
111 png_destroy_read_struct(&pngs, &pngi, 0);