/**
* Apply an orthographic projection matrix.
*
* \param left left clipping plane coordinate.
* \param right right clipping plane coordinate.
* \param bottom bottom clipping plane coordinate.
* \param top top clipping plane coordinate.
* \param nearval distance to the near clipping plane.
* \param farval distance to the far clipping plane.
*
* \sa glOrtho().
*
* Flushes vertices and validates parameters. Calls _math_matrix_ortho() with
* the top matrix of the current matrix stack and sets
* __struct gl_contextRec::NewState.
*/
void GLAPIENTRY
_mesa_Ortho( GLdouble left, GLdouble right,
GLdouble bottom, GLdouble top,
GLdouble nearval, GLdouble farval )
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glOrtho(%f, %f, %f, %f, %f, %f)\n",
left, right, bottom, top, nearval, farval);
if (left == right ||
bottom == top ||
nearval == farval)
{
_mesa_error( ctx, GL_INVALID_VALUE, "glOrtho" );
return;
}
_math_matrix_ortho( ctx->CurrentStack->Top,
(GLfloat) left, (GLfloat) right,
(GLfloat) bottom, (GLfloat) top,
(GLfloat) nearval, (GLfloat) farval );
ctx->NewState |= ctx->CurrentStack->DirtyFlag;
}
void
cogl_matrix_ortho (CoglMatrix *matrix,
float left,
float right,
float bottom,
float top,
float near_val,
float far_val)
{
#ifndef USE_MESA_MATRIX_API
CoglMatrix ortho;
/* column 0 */
ortho.xx = 2.0 / (right - left);
ortho.yx = 0.0;
ortho.zx = 0.0;
ortho.wx = 0.0;
/* column 1 */
ortho.xy = 0.0;
ortho.yy = 2.0 / (top - bottom);
ortho.zy = 0.0;
ortho.wy = 0.0;
/* column 2 */
ortho.xz = 0.0;
ortho.yz = 0.0;
ortho.zz = -2.0 / (far_val - near_val);
ortho.wz = 0.0;
/* column 3 */
ortho.xw = -(right + left) / (right - left);
ortho.yw = -(top + bottom) / (top - bottom);
ortho.zw = -(far_val + near_val) / (far_val - near_val);
ortho.ww = 1.0;
cogl_matrix_multiply (matrix, matrix, &ortho);
#else
_math_matrix_ortho (matrix, left, right, bottom, top, near_val, far_val);
#endif
_COGL_MATRIX_DEBUG_PRINT (matrix);
}
