1 /*************************************************************************** 2 * Copyright (c) 2024 Microsoft Corporation 3 * 4 * This program and the accompanying materials are made available under the 5 * terms of the MIT License which is available at 6 * https://opensource.org/licenses/MIT. 7 * 8 * SPDX-License-Identifier: MIT 9 **************************************************************************/ 10 11 12 /**************************************************************************/ 13 /**************************************************************************/ 14 /** */ 15 /** GUIX Component */ 16 /** */ 17 /** Scrollbar Management (Scrollbar) */ 18 /** */ 19 /**************************************************************************/ 20 21 #define GX_SOURCE_CODE 22 23 /* Include necessary system files. */ 24 25 #include "gx_api.h" 26 #include "gx_system.h" 27 #include "gx_display.h" 28 #include "gx_context.h" 29 #include "gx_widget.h" 30 #include "gx_utility.h" 31 #include "gx_scrollbar.h" 32 33 /**************************************************************************/ 34 /* */ 35 /* FUNCTION RELEASE */ 36 /* */ 37 /* _gx_scrollbar_thumb_position_calculate PORTABLE C */ 38 /* 6.1 */ 39 /* AUTHOR */ 40 /* */ 41 /* Kenneth Maxwell, Microsoft Corporation */ 42 /* */ 43 /* DESCRIPTION */ 44 /* */ 45 /* Calculate and return the position of a GX_SCROLLBAR thumb button */ 46 /* based scrollbar dimensions, current value, and visible range. */ 47 /* */ 48 /* */ 49 /* INPUT */ 50 /* */ 51 /* scroll Widget control block */ 52 /* */ 53 /* OUTPUT */ 54 /* */ 55 /* None */ 56 /* */ 57 /* CALLS */ 58 /* */ 59 /* _gx_context_pixelmap_get Retrieve pixelmap image */ 60 /* _gx_widget_resize Resize a widget */ 61 /* */ 62 /* CALLED BY */ 63 /* */ 64 /* Application Code */ 65 /* GUIX Internal Code */ 66 /* */ 67 /* RELEASE HISTORY */ 68 /* */ 69 /* DATE NAME DESCRIPTION */ 70 /* */ 71 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */ 72 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */ 73 /* resulting in version 6.1 */ 74 /* */ 75 /**************************************************************************/ _gx_scrollbar_thumb_position_calculate(GX_SCROLLBAR * scroll)76VOID _gx_scrollbar_thumb_position_calculate(GX_SCROLLBAR *scroll) 77 { 78 INT thumb_length = 0; 79 INT travelsize; 80 INT range; 81 INT space; 82 INT thumb_width; 83 INT scroll_width; 84 85 GX_RECTANGLE thumbrect; 86 ULONG style; 87 GX_PIXELMAP *thumb_pixelmap = NULL; 88 89 /* pick up scrollbar style */ 90 style = scroll -> gx_widget_style; 91 92 /* pick up the scroll width and thumb button width */ 93 94 thumb_width = scroll -> gx_scrollbar_appearance.gx_scroll_thumb_width; 95 96 /* see if the thumb has a pixelmap */ 97 if (scroll -> gx_scrollbar_appearance.gx_scroll_thumb_pixelmap) 98 { 99 _gx_widget_pixelmap_get((GX_WIDGET *) scroll, scroll -> gx_scrollbar_appearance.gx_scroll_thumb_pixelmap, &thumb_pixelmap); 100 } 101 102 if (style & GX_SCROLLBAR_VERTICAL) 103 { 104 scroll_width = scroll -> gx_widget_size.gx_rectangle_right - scroll -> gx_widget_size.gx_rectangle_left + 1; 105 106 travelsize = (scroll -> gx_widget_size.gx_rectangle_bottom - 107 scroll -> gx_widget_size.gx_rectangle_top) + 1; 108 } 109 else 110 { 111 scroll_width = scroll -> gx_widget_size.gx_rectangle_bottom - scroll -> gx_widget_size.gx_rectangle_top + 1; 112 113 travelsize = (scroll -> gx_widget_size.gx_rectangle_right - 114 scroll -> gx_widget_size.gx_rectangle_left) + 1; 115 } 116 117 travelsize -= scroll -> gx_scrollbar_appearance.gx_scroll_thumb_travel_max + 118 scroll -> gx_scrollbar_appearance.gx_scroll_thumb_travel_min; 119 120 range = scroll -> gx_scrollbar_info.gx_scroll_maximum - scroll -> gx_scrollbar_info.gx_scroll_minimum + 1; 121 122 if (style & GX_SCROLLBAR_RELATIVE_THUMB) 123 { 124 if (scroll -> gx_scrollbar_info.gx_scroll_maximum != 125 scroll -> gx_scrollbar_info.gx_scroll_minimum) 126 { 127 thumb_length = travelsize * scroll -> gx_scrollbar_info.gx_scroll_visible; 128 if (range) 129 { 130 thumb_length /= range; 131 } 132 if (thumb_length < thumb_width) 133 { 134 thumb_length = thumb_width; 135 } 136 } 137 } 138 else 139 { 140 if (thumb_pixelmap) 141 { 142 if (style & GX_SCROLLBAR_VERTICAL) 143 { 144 thumb_length = thumb_pixelmap -> gx_pixelmap_height; 145 thumb_width = thumb_pixelmap -> gx_pixelmap_width; 146 } 147 else 148 { 149 thumb_length = thumb_pixelmap -> gx_pixelmap_width; 150 thumb_width = thumb_pixelmap -> gx_pixelmap_height; 151 } 152 } 153 else 154 { 155 /* just a square thumb button */ 156 thumb_length = thumb_width; 157 } 158 } 159 space = (travelsize - thumb_length); 160 space *= scroll -> gx_scrollbar_info.gx_scroll_value - scroll -> gx_scrollbar_info.gx_scroll_minimum; 161 range -= scroll -> gx_scrollbar_info.gx_scroll_visible; 162 163 if (range) 164 { 165 space = (space + (range >> 1)) / range; 166 } 167 168 169 if((scroll -> gx_scrollbar_info.gx_scroll_value > scroll -> gx_scrollbar_info.gx_scroll_minimum) && 170 (scroll -> gx_scrollbar_info.gx_scroll_value + scroll -> gx_scrollbar_info.gx_scroll_visible - 1 < scroll -> gx_scrollbar_info.gx_scroll_maximum)) 171 { 172 if (space == 0) 173 { 174 space = 1; 175 } 176 else if (space == (travelsize - thumb_length)) 177 { 178 space -= 1; 179 } 180 } 181 182 thumbrect = scroll -> gx_widget_size; 183 184 if (style & GX_SCROLLBAR_VERTICAL) 185 { 186 thumbrect.gx_rectangle_left = (GX_VALUE)(thumbrect.gx_rectangle_left + (scroll_width - thumb_width) / 2); 187 thumbrect.gx_rectangle_right = (GX_VALUE) (thumbrect.gx_rectangle_left + thumb_width - 1); 188 thumbrect.gx_rectangle_top = (GX_VALUE)(scroll -> gx_widget_size.gx_rectangle_top + 189 scroll -> gx_scrollbar_appearance.gx_scroll_thumb_travel_min + space); 190 thumbrect.gx_rectangle_bottom = (GX_VALUE)(thumbrect.gx_rectangle_top + thumb_length - 1); 191 } 192 else 193 { 194 thumbrect.gx_rectangle_top = (GX_VALUE)(thumbrect.gx_rectangle_top + (scroll_width - thumb_width) / 2); 195 thumbrect.gx_rectangle_bottom = (GX_VALUE)(thumbrect.gx_rectangle_top + thumb_width - 1); 196 197 thumbrect.gx_rectangle_left = (GX_VALUE)(scroll -> gx_widget_size.gx_rectangle_left + 198 scroll -> gx_scrollbar_appearance.gx_scroll_thumb_travel_min + space); 199 thumbrect.gx_rectangle_right = (GX_VALUE)(thumbrect.gx_rectangle_left + thumb_length - 1); 200 } 201 202 _gx_widget_resize((GX_WIDGET *)&scroll -> gx_scrollbar_thumb, &thumbrect); 203 } 204 205
