nterm: fix scrolling

nterm/src/main.c

@@ -93,7 +93,7 @@ int main(int argc, char **argv) {
     terminal.pixelCount = terminal.width * terminal.height;
     terminal.pitch = terminal.width * 4;
     terminal.lineSize = terminal.pitch * 16;
-    terminal.totalSize = terminal.lineSize * terminal.height;
+    terminal.totalSize = terminal.pitch * terminal.height;
     terminal.cursor = 1;
     terminal.echo = 1;
     terminal.bg = ttyColors[0];
@@ -103,7 +103,7 @@ int main(int argc, char **argv) {
     terminal.redraw = 1;
 
     terminal.wchar = terminal.width / 8;
-    terminal.hchar = terminal.height / 8;
+    terminal.hchar = terminal.height / 16;
     terminal.x = 0;
     terminal.y = 0;
     terminal.buffer = malloc(terminal.pixelCount * 4);

nterm/src/render.c

@@ -10,6 +10,26 @@
 #include <unistd.h>
 #include <string.h>
 
+/* ntermDrawCursor(): draws the cursor on the frame buffer
+ * params: none
+ * returns: nothing
+ */
+
+void ntermDrawCursor() {
+    if(!terminal.cursor) return;
+
+    // get pixel offset
+    int x = terminal.x * 8;
+    int y = terminal.y * 16;
+    uint32_t *fb = (uint32_t *)((uintptr_t)terminal.buffer + (y * terminal.pitch) + (x * 4));
+
+    // I cursor
+    for(int i = 0; i < 16; i++) {
+        *fb = terminal.fg;
+        fb += terminal.width;
+    }
+}
+
 /* ntermCheckBoundaries(): checks the boundaries and scrolls if necessary
  * params: none
  * returns: 1 if scrolled, zero if not
@@ -23,8 +43,8 @@ int ntermCheckBoundaries() {
 
     if(terminal.y >= terminal.hchar) {
         // scroll up by one line
-        uint32_t *secondLine = (uint32_t *)((uintptr_t)terminal.buffer + (16*terminal.pitch));
-        size_t size = (terminal.hchar - 1) * 16 * terminal.pitch;
+        uint32_t *secondLine = (uint32_t *)((uintptr_t)terminal.buffer + terminal.lineSize);
+        size_t size = (terminal.hchar - 1) * terminal.lineSize;
         memcpy(terminal.buffer, secondLine, size);
 
         // clear the scrolled line, which is also pointed to by size
@@ -40,6 +60,8 @@ int ntermCheckBoundaries() {
         terminal.x = 0;
         terminal.y = terminal.hchar - 1;
 
+        if(terminal.cursor) ntermDrawCursor();
+
         // and update the entire screen
         lseek(terminal.lfb, 0, SEEK_SET);
         write(terminal.lfb, terminal.buffer, terminal.totalSize);
@@ -49,26 +71,6 @@ int ntermCheckBoundaries() {
     return 0;
 }
 
-/* ntermDrawCursor(): draws the cursor on the frame buffer
- * params: none
- * returns: nothing
- */
-
-void ntermDrawCursor() {
-    if(!terminal.cursor) return;
-
-    // get pixel offset
-    int x = terminal.x * 8;
-    int y = terminal.y * 16;
-    uint32_t *fb = (uint32_t *)((uintptr_t)terminal.buffer + (y * terminal.pitch) + (x * 4));
-
-    // I cursor
-    for(int i = 0; i < 16; i++) {
-        *fb = terminal.fg;
-        fb += terminal.width;
-    }
-}
-
 /* ntermEraseCursor(): erases the cursor from the frame buffer
  * params: none
  * returns: nothing
@@ -116,7 +118,8 @@ void ntermPutc(char c) {
 
         terminal.x = 0;
         terminal.y++;
-        ntermCheckBoundaries();
+        if(ntermCheckBoundaries()) return;
+
         ntermDrawCursor();
 
         ptr = (uint32_t *)((uintptr_t)terminal.buffer + (terminal.y * terminal.lineSize));