i_video_oled: increment tables now initialized when initializing

graphic mode.
cleanup.

Author: BrunoLevy

LiteX/software/Doom/mc1-doom/src/gen_oled_tables.c

@@ -1,7 +1,7 @@
-// Emacs style mode select   -*- C++ -*-
 //-----------------------------------------------------------------------------
 //
 //      DOOM graphics renderer for LiteX framebuffer
+//           (not part of mc1-doom)
 //
 //-----------------------------------------------------------------------------
 
@@ -76,20 +76,6 @@ void I_FinishUpdate (void) {
     */
 
 
-/*   
-    const unsigned char* src = (const unsigned char*)screens[0];
-    uint32_t* dst = fb_base + (FB_WIDTH-SCREENWIDTH)/2 +
-                              (FB_HEIGHT-SCREENHEIGHT)*FB_WIDTH/2;
-    
-    for (int y = 0; y < SCREENHEIGHT; ++y) {
-        for (int x = 0; x < SCREENWIDTH; ++x) {
-	   dst[x] = s_palette[src[x]];
-	}
-        src += SCREENWIDTH;
-        dst += FB_WIDTH;
-    }
-*/
-   
     const unsigned char* row_src = (const unsigned char*)screens[0];
     const unsigned char* row_src_end = row_src + SCREENWIDTH;
 

LiteX/software/Doom/mc1-doom/src/i_video_fb.c

@@ -1,7 +1,7 @@
-// Emacs style mode select   -*- C++ -*-
 //-----------------------------------------------------------------------------
 //
 //      DOOM graphics renderer for OLED display on LiteX LiteOS
+//               (not part of mc1-doom)
 //
 //-----------------------------------------------------------------------------
 
@@ -17,20 +17,28 @@
 
 static uint16_t s_palette[256] __attribute((section(".fastdata")));
 
-static const uint8_t
-oled_map_dx[OLED_WIDTH] /* __attribute((section(".fastdata"))) */ = {
-    0,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,
-    3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,
-    3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3,4,3,3
-};
-
-static const uint8_t
-oled_map_dy[OLED_HEIGHT] /* __attribute((section(".fastdata"))) */ = {
-    0,120,120,120,120,120,120,120,160,120,120,120,120,120,120,120,160,120,120,
-    120,120,120,120,120,160,120,120,120,120,120,120,120,160,120,120,120,120,
-    120,120,120,160,120,120,120,120,120,120,120,160,120,120,120,120,120,120,
-    120,160,120,120,120,120,120,120,120
-};
+/*
+   320x200 -> OLED_WIDTH x OLED_HEIGHT:
+   framebuffer pointer increment for next pixel
+*/
+static uint8_t oled_map_dx[OLED_WIDTH]   __attribute((section(".fastdata")));
+
+/*
+    320x200 -> OLED_WIDTH x OLED_HEIGHT:
+    framebuffer pointer increment for next line divided by 8 (shifted >> 3)
+*/
+static uint8_t oled_map_dy[OLED_HEIGHT]  __attribute((section(".fastdata")));
+
+static inline int map(int x, int in_max, int out_max) {
+    return x * in_max / out_max;
+}
+
+static inline int map_delta(int x, int in_max, int out_max) {
+    if(x == 0) {
+        return 0;
+    }
+    return map(x, in_max, out_max) - map(x-1, in_max, out_max);
+}
 
 void I_InitGraphics (void) {
    // Only initialize once.
@@ -39,8 +47,15 @@ void I_InitGraphics (void) {
      return;
    initialized = 1;
    screens[0] = (unsigned char*)malloc (SCREENWIDTH * SCREENHEIGHT);
-    if (screens[0] == NULL)
-        I_Error ("Couldn't allocate screen memory");
+   if (screens[0] == NULL)
+     I_Error ("Couldn't allocate screen memory");
+   for(int x=0; x<OLED_WIDTH; ++x) {
+      oled_map_dx[x] = (uint8_t)(map_delta(x, 320, OLED_WIDTH));
+   }
+   for(int y=0; y<OLED_HEIGHT; ++y) {
+      oled_map_dy[y] = (uint8_t)((map_delta(y, 200, OLED_HEIGHT)*320)>>3);
+   }
+   
    oled_init();
 }
 
@@ -61,82 +76,64 @@ void I_StartTic (void) {
 void I_UpdateNoBlit (void) {
 }
 
+
+//------------------------
+
+#ifdef CSR_OLED_SPI_BASE    
+
+// Wait for SPI driver to have finished sending data
 static inline void oled_wait(void) {
-#ifdef CSR_OLED_SPI_BASE
    while(oled_spi_status_read() != OLED_SPI_DONE);
-#endif   
 }
 
 // Same as in lite_oled, but does not change CS and CMD/DAT
+// and does not wait for SPI to have finished sending data
 static inline void oled_byte_raw(uint8_t b) {
-#ifdef CSR_OLED_SPI_BASE
    oled_spi_mosi_write(b);
    oled_spi_control_write(8*OLED_SPI_LENGTH | OLED_SPI_START);
-#endif
 }
 
 // Same as in lite_oled, but does not change CS and CMD/DAT
+// and does not wait for SPI to have finished sending data
 static inline void oled_data_uint16_raw(uint16_t RGB) {
+   // Unfortunately, in LiteX, the SPI driver can only send
+   // 8 bits at a time (the shifter is only 8 bits wide)
    oled_byte_raw((uint8_t)(RGB>>8));
    oled_wait();
    oled_byte_raw((uint8_t)(RGB));
 }
 
+#endif
+
+//------------------------
 
 void I_FinishUpdate (void) {
 
 #ifdef CSR_OLED_SPI_BASE    
     const unsigned char* src = (const unsigned char*)screens[0];
-    // Resolution / 4, a centered 80x50 window
     oled_write_window(0,0,OLED_WIDTH-1,OLED_HEIGHT-1);
     const unsigned char* line_ptr = src;
 
-    oled_ctl_out_write(OLED_SPI_DAT); 
+    // sending DATA to the SPI
+    oled_ctl_out_write(OLED_SPI_DAT);
+    // chip select ON (LOW)
     oled_spi_cs_write(OLED_SPI_CS_LOW);
     for(int y=0; y<OLED_HEIGHT; ++y) {
         const unsigned char* pixel_ptr = line_ptr;
         for(int x=0; x<OLED_WIDTH; ++x) {
             uint16_t pixelvalue = s_palette[*pixel_ptr];
-            oled_data_uint16_raw(pixelvalue);            
+	    // send pixel data to the SPI
+            oled_data_uint16_raw(pixelvalue);
+	    // increment framebuffer pointer 
             pixel_ptr += oled_map_dx[x];
+	    // wait for SPI write dat to be finished
             oled_wait();
         }
         line_ptr += (oled_map_dy[y]<<3);
     }
+    // chip select OFF (HIGH)
     oled_spi_cs_write(OLED_SPI_CS_HIGH);
 #endif
-
-/*    
-#ifdef CSR_OLED_SPI_BASE    
-    const unsigned char* src = (const unsigned char*)screens[0];
-    // Resolution / 4, a centered 80x50 window
-    oled_write_window(8,7,87,56);
-    const unsigned char* line_ptr = src;
-
-    oled_ctl_out_write(OLED_SPI_DAT); 
-    oled_spi_cs_write(OLED_SPI_CS_LOW);
-    for(int y=0; y<200; y+=4) {
-        for(int x=0; x<320; x+=4) {
-            uint16_t pixelvalue = s_palette[line_ptr[x]];
-            oled_data_uint16_raw(pixelvalue);
-        }
-        line_ptr += 4*320;
-    }
-    oled_spi_cs_write(OLED_SPI_CS_HIGH);
-#endif
-*/    
-    /*
-    float scaleX = (float)SCREENWIDTH / OLED_WIDTH;
-    float scaleY = (float)SCREENHEIGHT / OLED_HEIGHT;
-    for (uint8_t y = 0; y < OLED_HEIGHT; ++y) {
-        int iy = (int)(y * scaleY);
-        for(uint8_t x = 0; x < OLED_WIDTH; ++x){
-            int ix = (int)(x * scaleX);
-            uint16_t pixelvalue = s_palette[src[iy*SCREENWIDTH+ix]];
-            oled_setpixel_uint16(x, y, pixelvalue);
-        }
-    }
-    */
 }
 
 void I_ReadScreen (byte* scr) {