// Bind texture, preserve previous texture state
bool GnashTexture::bind()
{
TextureState * const ts = &_texture_state;
ts->old_texture = 0;
ts->was_bound = 0;
ts->was_enabled = glIsEnabled(GL_TEXTURE_2D);
if (!ts->was_enabled)
glEnable(GL_TEXTURE_2D);
else if (gl_get_param(GL_TEXTURE_BINDING_2D, &ts->old_texture))
ts->was_bound = _texture == ts->old_texture;
else
return false;
if (!ts->was_bound) {
gl_purge_errors();
glBindTexture(GL_TEXTURE_2D, _texture);
if (gl_check_error())
return false;
}
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
return true;
}
// glGetIntegerv() wrapper
static bool gl_get_param(GLenum param, unsigned int *pval)
{
GLint val;
gl_purge_errors();
glGetIntegerv(param, &val);
if (gl_check_error())
return false;
if (pval)
*pval = val;
return true;
}
/**
* gl_get_texture_param:
* @target: the target to which the texture is bound
* @param: the parameter name
* @pval: return location for the value
*
* This function is a wrapper around glGetTexLevelParameteriv() that
* does extra error checking.
*
* Return value: %TRUE on success
*/
gboolean
gl_get_texture_param(GLenum target, GLenum param, guint *pval)
{
GLint val;
gl_purge_errors();
glGetTexLevelParameteriv(target, 0, param, &val);
if (gl_check_error())
return FALSE;
if (pval)
*pval = val;
return TRUE;
}
/**
* gl_get_param:
* @param: the parameter name
* @pval: return location for the value
*
* This function is a wrapper around glGetIntegerv() that does extra
* error checking.
*
* Return value: %TRUE on success
*/
gboolean
gl_get_param(GLenum param, guint *pval)
{
GLint val;
gl_purge_errors();
glGetIntegerv(param, &val);
if (gl_check_error())
return FALSE;
if (pval)
*pval = val;
return TRUE;
}
/// Bind texture, preserve previous texture state
static bool bind_texture(TextureState *ts, GLenum target, GLuint texture)
{
ts->target = target;
ts->old_texture = 0;
ts->was_bound = 0;
ts->was_enabled = glIsEnabled(target);
GLenum texture_binding;
switch (target) {
case GL_TEXTURE_1D:
texture_binding = GL_TEXTURE_BINDING_1D;
break;
case GL_TEXTURE_2D:
texture_binding = GL_TEXTURE_BINDING_2D;
break;
case GL_TEXTURE_3D:
texture_binding = GL_TEXTURE_BINDING_3D;
break;
case GL_TEXTURE_RECTANGLE_ARB:
texture_binding = GL_TEXTURE_BINDING_RECTANGLE_ARB;
break;
default:
assert(!target);
return false;
}
if (!ts->was_enabled) {
glEnable(target);
} else if (gl_get_param(texture_binding, &ts->old_texture)) {
ts->was_bound = texture == ts->old_texture;
} else {
return false;
}
if (!ts->was_bound) {
gl_purge_errors();
glBindTexture(target, texture);
if (gl_check_error()) {
return false;
}
}
return true;
}