/************************************************************************************************************************************** * Project: discoverpixy * Website: https://github.com/t-moe/discoverpixy * Authors: Aaron Schmocker, Timo Lang * Institution: BFH Bern University of Applied Sciences * File: common/gui/button.c * * Version History: * Date Autor Email SHA Changes * 2015-04-27 timolang@gmail.com 7c9eabc Added button support. * 2015-05-17 timolang@gmail.com 2d46336 Improved comments in implementation of button, checkbox, numupdown, tft, touch and screen modules/submodules. * **************************************************************************************************************************************/ #include "tft.h" #include "touch.h" #include "button.h" #include /* The Idea is as follows: * When the user add's a button we create a touch area for that region and wait for PEN_DOWN events. * Once the user puts the pen down in this area we'll redraw the button with different shadows (feedback) * and we'll now wait on PEN_UP or PEN_LEAVE events. * If the user takes the pen away while in the area (PEN_UP), we call the provided user callback * Otherwise (PEN_LEAVE) we only restore the initial shadows */ /* Possible improvements: * Move the button by 1 pixel while he is pressed, to create a "full 3d" experience * Add events for the case when the button is pressed for a long time, without release */ //Method to calculate the shadow colors used to create the "3d" effect void calculate_shadows(uint16_t bgcolor, uint16_t* light_shadow, uint16_t* dark_shadow) { #define BRIGHTNESS_VAL 3 //How much the Brightness is in/decreased for button shadows (3 -> Add/Subtract 1/3 off Full Value) uint16_t c_light, c_dark; //c_light and c_dark will be filled with a lighter and a darker color as the background color (for the shadows) uint8_t r, g, b; //separate the channels of the 16-bit rgb565 color r = (bgcolor & 0xF800) >> 11; g = (bgcolor & 0x07E0) >> 5; b = (bgcolor & 0x001F) >> 0; //For the light shadow color: if ((r + 0x1F / BRIGHTNESS_VAL) > 0x1F) { //Adding one third would exceed the maximum of the red channel c_light = 0xF800; //Use full red } else { //adding one third to the red channel is fine c_light = (r + 0x1F / BRIGHTNESS_VAL) << 11; //Use same red as in the background, but add one third } if ((g + 0x3F / BRIGHTNESS_VAL) > 0x3F) { //same for the green channel c_light |= 0x07E0; } else { c_light |= (g + 0x3F / BRIGHTNESS_VAL) << 5; } if ((b + 0x1F / BRIGHTNESS_VAL) > 0x1F) { //and the blue channel c_light |= 0x0018; } else { c_light |= (b + 0x1F / BRIGHTNESS_VAL) << 0; } //For the dark shadow color if (r > (0x1F / BRIGHTNESS_VAL)) { //Subtracting one third would NOT exceed the minimum of the red channel c_dark = (r - 0x1F / BRIGHTNESS_VAL) << 11; //Use same red as in the background, but subtract one third } else { //Subtracting one third would give us a number below zero c_dark = 0x0000; //use no red channel } if (g > (0x3F / BRIGHTNESS_VAL)) { //Same for the green channel c_dark |= (g - 0x3F / BRIGHTNESS_VAL) << 5; } if (b > (0x1F / BRIGHTNESS_VAL)) { //and the blue channel c_dark |= (b - 0x1F / BRIGHTNESS_VAL) << 0; } //Assign the calculated shadows to out parameters if (light_shadow != NULL) { *light_shadow = c_light; } if (dark_shadow != NULL) { *dark_shadow = c_dark; } } //Callback which is called when the user touches the touch-area we created for the button void buttons_cb(void* touchArea, TOUCH_ACTION triggeredAction) { TOUCH_AREA_STRUCT* area = (TOUCH_AREA_STRUCT*)touchArea; BUTTON_STRUCT* button = (BUTTON_STRUCT*)touchArea; uint16_t c_light, c_dark; //c_light and c_dark will be filled with a lighter and a darker color as the background color (for the shadows) calculate_shadows(button->bgcolor, &c_light, &c_dark); switch (triggeredAction) { case PEN_DOWN: //If the user touches the area for the "first time" area->hookedActions = PEN_UP | PEN_LEAVE; //for the future we only want PEN_UP and PEN_LEAVE events //Draw shadows tft_draw_line(button->base.x1 + 1, button->base.y1, button->base.x2 - 1, button->base.y1, c_dark); //North tft_draw_line(button->base.x1, button->base.y1 + 1, button->base.x1, button->base.y2 - 1, c_dark); //West tft_draw_line(button->base.x1 + 1, button->base.y2, button->base.x2 - 1, button->base.y2, c_light); //South tft_draw_line(button->base.x2, button->base.y1 + 1, button->base.x2, button->base.y2 - 1, c_light); //East break; case PEN_UP: //If the user took the pen away, while in the area (=button pressed!) case PEN_LEAVE: //or the user "slided out" of the area area->hookedActions = PEN_DOWN; //for the future we only want PEN_DOWN events //Draw inverse shadows tft_draw_line(button->base.x1 + 1, button->base.y1, button->base.x2 - 1, button->base.y1, c_light); //North tft_draw_line(button->base.x1, button->base.y1 + 1, button->base.x1, button->base.y2 - 1, c_light); //West tft_draw_line(button->base.x1 + 1, button->base.y2, button->base.x2 - 1, button->base.y2, c_dark); //South tft_draw_line(button->base.x2, button->base.y1 + 1, button->base.x2, button->base.y2 - 1, c_dark); //East if (triggeredAction == PEN_UP && button->callback != NULL) { //If the button got "pressed" instead of left, and the user provided a callback button->callback(button); //execute the user callback } break; default: break; } } bool gui_button_add(BUTTON_STRUCT* button) { if (touch_have_empty(1)) { //Check if the touch module can handle one additional area //Calculate width and height of the button text unsigned int strwidth = tft_font_width(button->font) * strlen(button->text); unsigned char strheight = tft_font_height(button->font); button->base.hookedActions = PEN_DOWN; //At first we are interested in PEN_DOWN events button->base.callback = buttons_cb; //Use our own callback for the touch area events if (button->base.x2 == AUTO) { //The user wants us to calculate the button width automatically //Use string width + half of a character width as button width button->base.x2 = button->base.x1 - 1 + strwidth + (tft_font_width(button->font) / 2); } else if ((button->base.x2 - button->base.x1 + 1) < (strwidth + 2)) { //the provided width is too small to fit the entire text return false; //report error } if (button->base.y2 == AUTO) { //The user wants us to calculate the button height automatically //Use one and a half character heights as button height button->base.y2 = button->base.y1 - 1 + strheight + (strheight / 2); } else if ((button->base.y2 - button->base.y1 + 1) < (strheight + 2)) { //the provided height is too small to fit the text return false; } gui_button_redraw(button); //call the redraw method, which will take care of drawing the entire button return touch_register_area(&button->base); //Register the touch area and receive events for this button, from now on } return false; //no more touch areas left } void gui_button_redraw(BUTTON_STRUCT* button) { //Calculate text dimensions and shadow colors unsigned int strwidth = tft_font_width(button->font) * strlen(button->text); unsigned char strheight = tft_font_height(button->font); uint16_t c_light, c_dark; calculate_shadows(button->bgcolor, &c_light, &c_dark); //Draw the background and the 4 lines (shadow colors) tft_fill_rectangle(button->base.x1 + 1, button->base.y1 + 1, button->base.x2 - 1, button->base.y2 - 1, button->bgcolor); tft_draw_line(button->base.x1 + 1, button->base.y1, button->base.x2 - 1, button->base.y1, c_light); //North tft_draw_line(button->base.x1, button->base.y1 + 1, button->base.x1, button->base.y2 - 1, c_light); //West tft_draw_line(button->base.x1 + 1, button->base.y2, button->base.x2 - 1, button->base.y2, c_dark); //South tft_draw_line(button->base.x2, button->base.y1 + 1, button->base.x2, button->base.y2 - 1, c_dark); //East //Draw the text tft_print_line(button->base.x1 + (button->base.x2 - button->base.x1 + 1 - strwidth) / 2, button->base.y1 + (button->base.y2 - button->base.y1 + 1 - strheight) / 2, button->txtcolor, button->bgcolor, button->font, button->text); } void gui_button_remove(BUTTON_STRUCT* button) { //We only need to unregister the touch area, as we have not allocated anything else touch_unregister_area((TOUCH_AREA_STRUCT*)button); }