Graphics namespace includes rectangle, rounded rectangle, and circle

Also added methods to make writing to shm pool easier

src/graphics/mod.rs

@@ -0,0 +1,2 @@
+
+pub mod rectangle;

src/graphics/rectangle.rs

@@ -0,0 +1,43 @@
+
+use crate::wayland::shm::ShmPool;
+
+// l_row means local row and g_row means global row
+impl ShmPool {
+
+    // x and y are topleft corner of rect
+    pub fn rectangle(&mut self, x: usize, y: usize, w: usize, h: usize, color: u32) {
+        for g_row in y..y+h {
+            self.write(&vec![color; w], g_row*self.width+x);
+        }
+    }
+
+    // x and y and topleft corner of rect
+    pub fn rounded_rectangle(
+        &mut self,
+        x:      usize,
+        y:      usize,
+        w:      usize,
+        h:      usize,
+        radius: usize,
+        color:  u32
+    ) {
+        for l_row in 0..radius+1 {
+            let x_diff = radius - ((radius*radius - l_row*l_row) as f64).sqrt() as usize;
+            self.write(&vec![color; w - (2*x_diff)], (y+radius-l_row)*self.width + x + x_diff);
+            self.write(&vec![color; w - (2*x_diff)], (y+h-radius+l_row)*self.width + x + x_diff);
+        }
+        for g_row in y+radius..y+h-radius {
+            self.write(&vec![color; w], g_row*self.width+x);
+        }
+    }
+    
+    // x and y are center of circle
+    pub fn circle(&mut self, x: usize, y: usize, radius: usize, color: u32) {
+        for l_row in 0..radius { 
+            let x_diff = ((radius*radius - l_row*l_row) as f64).sqrt();
+            let mut row: Vec<u32> = vec![color; 2*x_diff as usize];
+            self.write(&row, (y+l_row)*self.width + x - x_diff as usize);
+            self.write(&row, (y-l_row)*self.width + x - x_diff as usize);
+        }
+    }
+}

src/main.rs

@@ -3,6 +3,7 @@ use std::error::Error;
 
 mod wayland;
 use wayland::wl_client::WlClient;
+mod graphics;
 
 fn main() -> Result<(), Box<dyn Error>> {
     let mut wl_client = WlClient::new()?;

src/wayland/shm.rs

@@ -2,14 +2,17 @@ use libc::{c_void, ftruncate, mmap, munmap, shm_open, shm_unlink, MAP_FAILED, MA
 
 #[derive(Clone)]
 pub struct ShmPool {
-    pub fd: i32,
-    pub id: u32,
-    pub addr: *mut c_void,
-    pub size: usize,
+    pub fd:     i32,
+    pub id:     u32,
+    pub addr:   *mut c_void,
+    pub size:   usize,
+    pub width:  usize,
 }
 
 impl ShmPool {
-    pub fn new(size: usize, id: u32) -> std::io::Result<ShmPool> {
+    pub fn new(width: usize, height: usize, id: u32) -> std::io::Result<ShmPool> {
+        let size = width * height * 4;
+
         let shm_path: *const i8 = b"/chlorostart\0".as_ptr() as *const i8;
         let fd = unsafe { shm_open(shm_path, O_RDWR | O_EXCL | O_CREAT, 0o600) };
         if fd == -1 {
@@ -37,7 +40,8 @@ impl ShmPool {
             fd,
             id,
             addr,
-            size 
+            size,
+            width,
         })
     }
 
@@ -50,17 +54,31 @@ impl ShmPool {
         Ok(())
     }
 
-    pub fn write(&mut self, data: &Vec<u32>, offset: isize) -> std::io::Result<()> {
-        // TODO: Bounds check
+    pub fn write(&mut self, data: &Vec<u32>, offset: usize) {
+        if offset > self.size {
+            return;
+        }
         unsafe {
             std::ptr::copy_nonoverlapping(
                 data.as_ptr() as *const u32, // src: data as *const u32
-                self.addr.offset(offset*4) as *mut u32, // dst: ShmPool address as *mut u32
-                data.len()
+                self.addr.offset(4*offset as isize) as *mut u32, // dst: ShmPool address as *mut u32
+                if offset + data.len() * 4 <= self.size {
+                    data.len()
+                } else {
+                    data.len() - offset
+                }
             );
         }
+    }
 
-        Ok(())
+    pub fn write_pixel(&mut self, data: u32, offset: isize) {
+        // TODO: Bounds check
+        unsafe {*(self.addr.offset(offset*4) as *mut u32) = data;}
+    }
+
+    pub fn read_pixel(&self, offset: usize) -> u32 {
+        // TODO: Bounds check
+        return unsafe {*(self.addr.offset(4*offset as isize) as *const u32)};
     }
 }
 

src/wayland/wl_shm.rs

@@ -11,8 +11,11 @@ impl WlClient {
 
     pub fn wl_shm_create_pool(&mut self, width: usize, height: usize) -> Result<(), Box<dyn Error>> {
         self.current_id += 1;
-        self.shm_pool = Some(shm::ShmPool::new(width * height * STRIDE, self.current_id)?);
-        self.shm_pool.as_mut().unwrap().write(&vec![0xffff0000; width * height], 0)?;
+        self.shm_pool = Some(shm::ShmPool::new(width, height, self.current_id)?);
+        self.shm_pool.as_mut().unwrap().write(&vec![0xffff0000; width * height], 0);
+        self.shm_pool.as_mut().unwrap().rectangle(50, 50, 50, 50, 0xff00ff00);
+        self.shm_pool.as_mut().unwrap().circle(200, 200, 50, 0xff0000ff);
+        self.shm_pool.as_mut().unwrap().rounded_rectangle(400, 200, 200, 100, 14, 0xffffff00);
 
         let object = self.shm_id.ok_or(UnsetErr("shm_id".to_string()))?;
         const OPCODE: u16 = 0;