208 lines
7.2 KiB
C
208 lines
7.2 KiB
C
/***************************************************************************
|
|
* Copyright (C) 2020 by Federico Izzo IU2NUO, Niccolò Izzo IU2KIN and *
|
|
* Silvano Seva IU2KWO *
|
|
* *
|
|
* This program is free software; you can redistribute it and/or modify *
|
|
* it under the terms of the GNU General Public License as published by *
|
|
* the Free Software Foundation; either version 3 of the License, or *
|
|
* (at your option) any later version. *
|
|
* *
|
|
* This program is distributed in the hope that it will be useful, *
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
|
|
* GNU General Public License for more details. *
|
|
* *
|
|
* You should have received a copy of the GNU General Public License *
|
|
* along with this program; if not, see <http://www.gnu.org/licenses/> *
|
|
***************************************************************************/
|
|
|
|
/**
|
|
* This driver provides an lcd screen emulator to allow UI development and
|
|
* testing on a x86/x64 computer.
|
|
* Graphics control is provided through SDL2 library, you need to have the SDL2
|
|
* development library installed on your machine to compile and run code using
|
|
* this driver.
|
|
*/
|
|
|
|
#include "display.h"
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <SDL2/SDL.h>
|
|
|
|
#undef main /* necessary to avoid conflicts with SDL_main */
|
|
|
|
/*
|
|
* Screen dimensions, adjust basing on the size of the screen you need to
|
|
* emulate
|
|
*/
|
|
#ifndef SCREEN_WIDTH
|
|
#define SCREEN_WIDTH 160
|
|
#endif
|
|
|
|
#ifndef SCREEN_HEIGHT
|
|
#define SCREEN_HEIGHT 128
|
|
#endif
|
|
|
|
#if !defined(PIX_FMT_BW) && !defined(PIX_FMT_GRAYSC) && !defined(PIX_FMT_RGB565)
|
|
#warning No pixel format defined, defaulting to RGB565
|
|
#define PIX_FMT_RGB565
|
|
#endif
|
|
|
|
SDL_Renderer *renderer; /* SDL renderer */
|
|
SDL_Window *window; /* SDL window */
|
|
SDL_Texture *displayTexture; /* SDL rendering surface */
|
|
void *frameBuffer; /* Pointer to framebuffer */
|
|
bool inProgress; /* Flag to signal when rendering is in progress */
|
|
|
|
/**
|
|
* @internal
|
|
* Internal helper function which fetches pixel at position (x, y) from framebuffer
|
|
* and returns it in SDL-compatible format, which is ARGB8888.
|
|
*/
|
|
uint32_t fetchPixelFromFb(unsigned int x, unsigned int y) {
|
|
uint32_t pixel = 0;
|
|
|
|
#ifdef PIX_FMT_BW
|
|
/*
|
|
* Black and white 1bpp format: framebuffer is an array of uint8_t, where
|
|
* each cell contains the values of eight pixels, one per bit.
|
|
*/
|
|
uint8_t *fb = (uint8_t *)(frameBuffer);
|
|
unsigned int cell = (x + y*SCREEN_WIDTH) / 8;
|
|
unsigned int elem = (x + y*SCREEN_WIDTH) % 8;
|
|
if(fb[cell] & (1 << elem)) pixel = 0xFFFFFFFF;
|
|
#endif
|
|
|
|
#ifdef PIX_FMT_GRAYSC
|
|
/*
|
|
* Convert from 8bpp grayscale to ARGB8888, we have to do nothing more that
|
|
* replicating the pixel value for the three components
|
|
*/
|
|
uint8_t *fb = (uint8_t *)(frameBuffer);
|
|
uint8_t px = fb[x + y*SCREEN_WIDTH];
|
|
|
|
pixel = 0xFF000000 | (px << 16) | (px << 8) | px;
|
|
#endif
|
|
|
|
#ifdef PIX_FMT_RGB565
|
|
/*
|
|
* SDL pixel format is ARGB8888, while ours is RGB565, thus we need
|
|
* to do some conversions when writing framebuffer content to the
|
|
* window. We also set alpha value to its maximum.
|
|
*/
|
|
uint16_t *fb = (uint16_t *) (frameBuffer);
|
|
|
|
uint32_t r = (fb[x + y * SCREEN_WIDTH] & 0xF800) >> 11;
|
|
uint32_t g = (fb[x + y * SCREEN_WIDTH] & 0x07E0) >> 5;
|
|
uint32_t b = (fb[x + y * SCREEN_WIDTH] & 0x001F) & 0x1F;
|
|
|
|
/*
|
|
* Here we do conversions by multiplying by some scaling factors,
|
|
* we use ints just because the precision of floats is not really
|
|
* needed.
|
|
* Conversion factors:
|
|
* - five bit to eight bit: 8.226
|
|
* - six bit to eight bit: 4.0476
|
|
*/
|
|
r = (r * 8) + (r * 226) / 1000;
|
|
g = (g * 4) + (g * 476) / 10000;
|
|
b = (b * 8) + (b * 226) / 1000;
|
|
|
|
pixel = 0xFF000000 | (r << 16) | (g << 8) | b;
|
|
#endif
|
|
|
|
return pixel;
|
|
}
|
|
|
|
|
|
void display_init() {
|
|
if (SDL_Init(SDL_INIT_VIDEO) < 0) {
|
|
printf("SDL video init error!!\n");
|
|
|
|
} else {
|
|
|
|
window = SDL_CreateWindow("OpenRTX",
|
|
SDL_WINDOWPOS_UNDEFINED,
|
|
SDL_WINDOWPOS_UNDEFINED,
|
|
SCREEN_WIDTH * 3, SCREEN_HEIGHT * 3,
|
|
SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE);
|
|
|
|
renderer = SDL_CreateRenderer(window, -1, 0);
|
|
SDL_RenderSetLogicalSize(renderer, SCREEN_WIDTH, SCREEN_HEIGHT);
|
|
displayTexture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STREAMING,
|
|
SCREEN_WIDTH, SCREEN_HEIGHT);
|
|
SDL_RenderClear(renderer);
|
|
SDL_RenderCopy(renderer, displayTexture, NULL, NULL);
|
|
SDL_RenderPresent(renderer);
|
|
|
|
/*
|
|
* Black and white pixel format: framebuffer type is uint8_t where each
|
|
* bit represents a pixel. We have to allocate
|
|
* (SCREEN_HEIGHT * SCREEN_WIDTH)/8 elements
|
|
*/
|
|
#ifdef PIX_FMT_BW
|
|
unsigned int fbSize = (SCREEN_HEIGHT * SCREEN_WIDTH)/8;
|
|
if((fbSize * 8) < (SCREEN_HEIGHT * SCREEN_WIDTH)) fbSize += 1; /* Compensate for eventual truncation error in division */
|
|
fbSize *= sizeof(uint8_t);
|
|
#endif
|
|
|
|
/*
|
|
* Grayscale pixel format: framebuffer type is uint8_t where each element
|
|
* controls one pixel
|
|
*/
|
|
#ifdef PIX_FMT_GRAYSC
|
|
unsigned int fbSize = SCREEN_HEIGHT * SCREEN_WIDTH * sizeof(uint8_t);
|
|
#endif
|
|
|
|
/*
|
|
* RGB565 pixel format: framebuffer type is uint16_t where each element
|
|
* controls one pixel
|
|
*/
|
|
#ifdef PIX_FMT_RGB565
|
|
unsigned int fbSize = SCREEN_HEIGHT * SCREEN_WIDTH * sizeof(uint16_t);
|
|
#endif
|
|
|
|
frameBuffer = malloc(fbSize);
|
|
memset(frameBuffer, 0xFFFF, fbSize);
|
|
inProgress = false;
|
|
}
|
|
}
|
|
|
|
void display_terminate() {
|
|
while (inProgress) {} /* Wait until current render finishes */
|
|
printf("Terminating SDL display emulator, goodbye!\n");
|
|
free(frameBuffer);
|
|
SDL_DestroyWindow(window);
|
|
SDL_Quit();
|
|
}
|
|
|
|
void display_renderRows(uint8_t startRow, uint8_t endRow) {
|
|
Uint32 *pixels;
|
|
int pitch = 0;
|
|
if (SDL_LockTexture(displayTexture, NULL, (void **) &pixels, &pitch) < 0) {
|
|
printf("SDL_lock failed: %s\n", SDL_GetError());
|
|
}
|
|
inProgress = true;
|
|
for (unsigned int x = 0; x < SCREEN_WIDTH; x++) {
|
|
for (unsigned int y = startRow; y < endRow; y++) {
|
|
pixels[x + y * SCREEN_WIDTH] = fetchPixelFromFb(x, y);
|
|
}
|
|
}
|
|
SDL_UnlockTexture(displayTexture);
|
|
SDL_RenderCopy(renderer, displayTexture, NULL, NULL);
|
|
SDL_RenderPresent(renderer);
|
|
inProgress = false;
|
|
}
|
|
|
|
void display_render() {
|
|
display_renderRows(0, SCREEN_HEIGHT);
|
|
}
|
|
|
|
bool display_renderingInProgress() {
|
|
return inProgress;
|
|
}
|
|
|
|
void *display_getFrameBuffer() {
|
|
return (void *) (frameBuffer);
|
|
}
|