c++ - DevIL image not rendering correctly -

i using opengl, can load tga files properly, reason when render jpg files, not see them correctly.

this image supposed like--

and looks like.. why stretched? because of coordinates?

here code using drawing.

void renderer::drawjpg(gluint tex, int xi, int yq, int width, int height) const { glbindtexture(gl_texture_2d, tex); glbegin(gl_quads); gltexcoord2i(0, 0); glvertex2i(0+xi,   0+xi); gltexcoord2i(0, 1); glvertex2i(0+xi,   height+xi); gltexcoord2i(1, 1); glvertex2i(width+xi, height+xi); gltexcoord2i(1, 0); glvertex2i(width+xi, 0+xi); glend(); } 

this how loading image...

imagename=s; ilboolean success; ilinit(); ilgenimages(1, &id); ilbindimage(id); success = illoadimage((const ilstring)imagename.c_str()); if (success) {     success = ilconvertimage(il_rgb, il_unsigned_byte); /* convert every colour component                                                          unsigned byte. if image contains alpha channel can replace il_rgb il_rgba */     if (!success)     {         printf("image conversion failed.");     }     glgentextures(1, &id);     glbindtexture(gl_texture_2d, id);      width = ilgetinteger(il_image_width);     height = ilgetinteger(il_image_height);      glteximage2d(gl_texture_2d, 0, ilgetinteger(il_image_bpp), ilgetinteger(il_image_width),                  ilgetinteger(il_image_height), 0, ilgetinteger(il_image_format), gl_unsigned_byte,                  ilgetdata());     gltexparameteri(gl_texture_2d, gl_texture_wrap_s, gl_repeat);       // linear filtered     gltexparameteri(gl_texture_2d, gl_texture_wrap_t, gl_repeat);       // linear filtered     gltexparameteri(gl_texture_2d, gl_texture_mag_filter, gl_linear);     gltexparameteri(gl_texture_2d, gl_texture_min_filter, gl_linear); 

i should mention this, images did rendered properly, thought because width != height. not case, images width != height loaded fine. other images still problem.

you need call

glpixelstorei(gl_unpack_alignment, 1); 

before uploading texture data glteximage2d.

from reference pages:

gl_unpack_alignment

specifies alignment requirements start of each pixel row in memory. allowable values 1 (byte-alignment), 2 (rows aligned even-numbered bytes), 4 (word-alignment), , 8 (rows start on double-word boundaries).

the default value alignment 4 , image loading library returns pixel data byte-aligned rows, explains why of images ok (when width multiple of four).