void Offscreen::set(const Texture & in)
{
//DJV_DEBUG("Offscreen::set");
fbo_check();
DJV_DEBUG_GL(glFramebufferTexture2D(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
GL_TEXTURE_RECTANGLE,
in.id(),
0));
}
void board_init(const GLuint aWidth, const GLuint aKnightRow, const GLuint aKnightCol)
{
board__width = aWidth;
// number of cycles it takes to finish the computation:
//
// (3 cycles per knight) * (number of knights)
//
// the -1 is because the initial knight is not determined
// at runtime, so we save one cycle of processing.
//
// see EXPORT_DELAY in the "naive.cg.erb" file for details.
//
board__numCycles = 3 * board__area;
printf("\nThe tour should take %lu cycles to complete.\n", board__numCycles);
// generate the board data
if((board__data = (float*)malloc(4*board__area*sizeof(float))) == NULL)
{
printf("\n*** out of memory allocating board__data ***\n");
exit(2);
}
unsigned addr = 0;
for(unsigned row = 0; row < board__width; row++) {
for (unsigned col = 0; col < board__width; col++) {
// red channel
board__data[addr++] = (
// set initial position of knight
row == aKnightRow &&
col == aKnightCol
) ? 1 : 0;
// green channel
board__data[addr++] = 0;
// blue channel
board__data[addr++] = 0;
// alpha channel
board__data[addr++] = 8; // 8 is MOVE_NONE (see naive.cg.erb for details); all cells should have next move = NONE initially, because only the knight makes the "next move" desicison at *runtime*
}
}
// Generate, set up, and bind the texture
texture_new(&board__computeTexture, board__width, board__width, GL_TEXTURE_RECTANGLE_ARB, GL_RGBA32F_ARB, NULL);
// initialize the FBO
fbo_init(board__width, board__width);
// Attach the texture to the framebuffer object
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_RECTANGLE_ARB, board__computeTexture, 0);
// Check the FBO for completeness
fbo_check();
// generate texture for board display
texture_new(&board__displayTexture, board__width, board__width, GL_TEXTURE_2D, GL_RGBA, NULL);
// generate OpenGL display lists to speed up rendering
board__gridDisplayList = glGenLists(1);
glNewList(board__gridDisplayList, GL_COMPILE);
// draw board outline (grid)
float step = 2.0 / board__width;
float cell;
glBegin(GL_LINES);
// draw rows
for (cell = -1 + step; cell < board__width; cell += step) {
glVertex3f(-1, cell, -1);
glVertex3f(1, cell, -1);
}
// draw columns
for (cell = -1 + step; cell < board__width; cell += step) {
glVertex3f(cell, -1, -1);
glVertex3f(cell, 1, -1);
}
glEnd();
glEndList();
}
