copy/paste for removing hexes

src/hexgame.cpp

@@ -199,6 +199,13 @@ handleMouseDown(SDL_MouseButtonEvent &e)
 				hgAddHex(gs->grid, xsect, rs->filled_hex_render_group, rs->hex_line_render_group);
 			break;
 		}
+		case REMOVE_HEXES: {
+			v3f ray = cameraCreateRay(rs->cam, coords, dims);
+			v3f xsect;
+			if (cameraIntersectPlane(rs->cam, ray, gs->grid.position, gs->grid.normal, xsect))
+				hgRemoveHex(gs->grid, xsect, rs->filled_hex_render_group, rs->hex_line_render_group);
+			break;
+		}
 		case NONE:
 		default:
 			v2f v = cameraUnproject(rs->cam, coords.x, coords.y, dims.x, dims.y);

src/hexgrid.cpp

@@ -119,8 +119,55 @@ hgAddHex(hexgrid& hg, v3f hex_coords, render_group* rg_filled, render_group* rg_
 }
 
 bool
-hgRemoveHex(hexgrid& hg, v3i hex_coords)
+hgRemoveHex(hexgrid& hg, v3f hex_coords, render_group* rg_filled, render_group* rg_lines)
 {
+	hex_info* hxi = hgGetSingleHex(hg, hex_coords.x, hex_coords.y);
+	if (hxi) {
+		render_object* ro_f = rg_filled->render_objects[0];
+		gl_buffer& vb_f = ro_f->vertex_buffer;
+		gl_buffer& nb_f = ro_f->normal_buffer;
+		gl_buffer& ub_f = ro_f->uv_buffer;
+		render_object* ro_l = rg_lines->render_objects[0];
+		gl_buffer& vb_l = ro_l->vertex_buffer;
+		gl_buffer& nb_l = ro_l->normal_buffer;
+		gl_buffer& ub_l = ro_l->uv_buffer;
+
+		// NOTE: don't need sanity checks to delete from buffers
+		vb_f.count -= IDX_PER_HEX_FILLED;
+		nb_f.count -= IDX_PER_HEX_FILLED;
+		ub_f.count -= IDX_PER_HEX_FILLED;
+		vb_l.count -= IDX_PER_HEX_LINES;
+		nb_l.count -= IDX_PER_HEX_LINES;
+		ub_l.count -= IDX_PER_HEX_LINES;
+
+		assert(hg.hex_map.erase(hxi->hex) == 1);
+
+		// NOTE: have to repopulate all the buffers, and re-index
+		uint i = 0;
+		for (auto it : hg.hex_map) {
+			it.second.hexID = i;
+			populateFilledHexGLBuffers(hg, it.second, rg_filled);
+			populateLineGLBuffers(hg, it.second, rg_lines);
+			i++;
+		}
+
+		// NOTE: we do need to update the whole buffer when removing data
+		glBindBuffer(GL_ARRAY_BUFFER, vb_f.buffer_id);
+		glBufferSubData(GL_ARRAY_BUFFER, 0, vb_f.count * sizeof(GLfloat), vb_f.buffer);
+		glBindBuffer(GL_ARRAY_BUFFER, nb_f.buffer_id);
+		glBufferSubData(GL_ARRAY_BUFFER, 0, nb_f.count * sizeof(GLfloat), nb_f.buffer);
+		glBindBuffer(GL_ARRAY_BUFFER, ub_f.buffer_id);
+		glBufferSubData(GL_ARRAY_BUFFER, 0, ub_f.count * sizeof(GLfloat), ub_f.buffer);
+		glBindBuffer(GL_ARRAY_BUFFER, vb_l.buffer_id);
+		glBufferSubData(GL_ARRAY_BUFFER, 0, vb_l.count * sizeof(GLfloat), vb_l.buffer);
+		glBindBuffer(GL_ARRAY_BUFFER, nb_l.buffer_id);
+		glBufferSubData(GL_ARRAY_BUFFER, 0, nb_l.count * sizeof(GLfloat), nb_l.buffer);
+		glBindBuffer(GL_ARRAY_BUFFER, ub_l.buffer_id);
+		glBufferSubData(GL_ARRAY_BUFFER, 0, ub_l.count * sizeof(GLfloat), ub_l.buffer);
+
+		return true;
+	}
+
 	return false;
 }
 

src/hexgrid.h

@@ -89,7 +89,7 @@ bool hgInit(hexgrid& hg, render_group* rg_filled, render_group* rg_lines);
 
 bool hgAddHex(hexgrid& hg, v3f hex_coords, render_group* rg_filled, render_group* rg_lines);
 
-bool hgRemoveHex(hexgrid& hg, v3i hex_coords);
+bool hgRemoveHex(hexgrid& hg, v3f hex_coords, render_group* rg_filled, render_group* rg_lines);
 
 // -------------------