rework daguerre a bit

applications/init/source/main.cpp

@@ -1,23 +1,37 @@
 #include <daguerre.hpp>
 
-void alpha_overlay(
+static daguerre::hilbert_color transparent_color;
-  daguerre::hilbert_color &dest, const daguerre::rgb24 &src) {
-  if (src.r != 0xff || src.g != 0x00 || src.b != 0xff)
-    daguerre::default_overlay(dest, src);
-}
 
-void invert(daguerre::rgb24 &dest, const daguerre::rgb24 &src) {
+void alpha_overlay(
-  dest.r = 255 - src.r;
+  daguerre::hilbert_color &dest, const daguerre::hilbert_color &src) {
-  dest.g = 255 - src.g;
+  if (src != transparent_color)
-  dest.b = 255 - src.b;
+    dest = src;
 }
 
 int main(int, char **) {
 
-  auto framebuffer = daguerre::get_hilbert_framebuffer();
+  daguerre::default_overlay(
+    transparent_color, (daguerre::rgb24){.r = 255, .g = 0, .b = 255});
 
-  daguerre::image<daguerre::rgb24> burden;
+  auto raw_framebuffer = daguerre::get_hilbert_framebuffer();
-  daguerre::try_load_ppm("/assets/burden.ppm", burden);
+  const unsigned fbw = raw_framebuffer.width;
+  const unsigned fbh = raw_framebuffer.height;
+
+  daguerre::image<daguerre::rgb24> raw_burden;
+  daguerre::try_load_ppm("/assets/burden.ppm", raw_burden);
+
+  daguerre::image<daguerre::rgb24> burden_stretch(fbw, fbh);
+  daguerre::image<daguerre::rgb24> burden_stretch_inverted(fbw, fbh);
+  for (unsigned y = 0; y < fbh; ++y)
+    for (unsigned x = 0; x < fbw; ++x) {
+      daguerre::rgb24 color = raw_burden.get(
+        x * raw_burden.width / fbw, y * raw_burden.height / fbh);
+      burden_stretch.set(x, y, color);
+      burden_stretch_inverted.set(x, y, {
+        .r = (uint8_t)(255 - color.r),
+        .g = (uint8_t)(255 - color.g),
+        .b = (uint8_t)(255 - color.b)});
+    }
 
   daguerre::image<daguerre::rgb24> pointer;
   daguerre::try_load_ppm("/assets/pointer.ppm", pointer);
@@ -25,54 +39,64 @@ int main(int, char **) {
   daguerre::fixed_bitmap_font<bool> terminus;
   daguerre::try_load_psf("/assets/terminus-bold-18x10.psf", terminus);
 
-  terminus.overlay_text<>(burden, 0, 0, "this is a test");
+  terminus.overlay_text<>(burden_stretch, 0, 0, "this is a test");
+  terminus.overlay_text<>(burden_stretch_inverted, 0, 0, "tset a si siht");
 
-  int32_t width = burden.width < framebuffer.width
+  daguerre::image<daguerre::hilbert_color>
-                ? burden.width : framebuffer.width;
+    burden_stretch_hilbert(burden_stretch);
-  int32_t height = burden.height < framebuffer.height
-                 ? burden.height : framebuffer.height;
-  unsigned x = (framebuffer.width - width) / 2;
-  unsigned y = (framebuffer.height - height) / 2;
 
-  int32_t new_mouse_x = width / 2;
+  daguerre::image<daguerre::hilbert_color>
-  int32_t new_mouse_y = height / 2;
+    burden_stretch_inverted_hilbert(burden_stretch_inverted);
-  int32_t old_mouse_x = new_mouse_x;
+
-  int32_t old_mouse_y = new_mouse_y;
+  daguerre::image<daguerre::hilbert_color> pointer_hilbert(pointer);
+
+  daguerre::image<daguerre::hilbert_color> double_buffer(
+    fbw + pointer.width - 1, fbh + pointer.height - 1);
+
+  int32_t mouse_x = fbw / 2;
+  int32_t mouse_y = fbh / 2;
   bool was_left_mouse_down = false;
 
-  daguerre::overlay_region<>(framebuffer, x, y, burden, 0, 0, width, height);
+  bool should_draw = true;
 
   while (1) {
 
+    if (should_draw) {
+      double_buffer.overlay_from<>(
+        burden_stretch_hilbert, 0, 0, 0, 0, fbw, fbh);
+      double_buffer.overlay_from<daguerre::hilbert_color, alpha_overlay>(
+        pointer_hilbert, mouse_x, mouse_y,
+        0, 0, pointer.width, pointer.height);
+      raw_framebuffer.overlay_from<>(double_buffer, 0, 0, 0, 0, fbw, fbh);
+      should_draw = false;
+    }
+
     __euler_mouse_buttons mouse_buttons;
     int16_t mouse_change_x, mouse_change_y;
     uint32_t key_packet;
     __euler_input_packet_type packet_type = __euler_get_input_packet(
       mouse_buttons, mouse_change_x, mouse_change_y, key_packet);
 
-    bool anything_changed = false;
     bool should_invert = false;
 
     if (packet_type == __EULER_IPT_MOUSE) {
 
       if (mouse_change_x != 0 || mouse_change_y != 0) {
 
-        old_mouse_x = new_mouse_x;
+        mouse_x += mouse_change_x;
-        old_mouse_y = new_mouse_y;
+        mouse_y += mouse_change_y;
-        new_mouse_x += mouse_change_x;
-        new_mouse_y += mouse_change_y;
 
-        if (new_mouse_x < 0)
+        if (mouse_x < 0)
-          new_mouse_x = 0;
+          mouse_x = 0;
-        else if ((unsigned)new_mouse_x > width - pointer.width)
+        else if ((unsigned)mouse_x >= fbw)
-          new_mouse_x = width - pointer.width;
+          mouse_x = fbw - 1;
 
-        if (new_mouse_y < 0)
+        if (mouse_y < 0)
-          new_mouse_y = 0;
+          mouse_y = 0;
-        else if ((unsigned)new_mouse_y > height - pointer.height)
+        else if ((unsigned)mouse_y >= fbh)
-          new_mouse_y = height - pointer.height;
+          mouse_y = fbh - 1;
 
-        anything_changed = true;
+        should_draw = true;
 
       }
 
@@ -88,28 +112,8 @@ int main(int, char **) {
         should_invert = true;
 
     if (should_invert) {
-
+      daguerre::swap(burden_stretch_hilbert, burden_stretch_inverted_hilbert);
-      //this works with the current implementation of overlay_region, but
+      should_draw = true;
-      //maybe it would be better to have a dedicated function for when the
-      //two regions are exactly the same, given the comment on overlay_region.
-      daguerre::overlay_region<daguerre::rgb24, daguerre::rgb24, invert>(
-        burden, 0, 0, burden, 0, 0, width, height);
-
-      daguerre::overlay_region<>(
-        framebuffer, x, y, burden, 0, 0, width, height);
-
-      anything_changed = true;
-
-    }
-
-    if (anything_changed) {
-      daguerre::overlay_region<>(
-        framebuffer, old_mouse_x + x, old_mouse_y + y, burden,
-        old_mouse_x, old_mouse_y, pointer.width, pointer.height);
-      daguerre::overlay_region<
-        daguerre::hilbert_color, daguerre::rgb24, alpha_overlay>(
-        framebuffer, new_mouse_x + x, new_mouse_y + y,
-        pointer, 0, 0, pointer.width, pointer.height);
     }
 
   }

euler/include/algorithm

@@ -0,0 +1,12 @@
+#pragma once
+
+namespace std {
+
+  template <class t>
+  void swap(t &a, t &b) {
+    t tmp = a;
+    a = b;
+    b = tmp;
+  }
+
+}

libraries/daguerre/include/daguerre.hpp

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <algorithm>
 #include <stdint.h>
 #include <cstring>
 #include <cstdio>
@@ -14,6 +15,11 @@ namespace daguerre {
     uint8_t b;
   };
 
+  template <class color_t>
+  static inline void default_overlay(color_t &dest, const color_t &src) {
+    dest = src;
+  }
+
   static inline void default_overlay(hilbert_color &dest, const rgb24 &src) {
     dest = __euler_encode_color(src.r, src.g, src.b);
   }
@@ -53,7 +59,14 @@ namespace daguerre {
         delete[] buffer;
     }
 
-    image(const image<color_t> &other) = delete;
+    template <class other_color_t,
+      void overlay(color_t &, const other_color_t &) = default_overlay>
+    image(const image<other_color_t> &other)
+    : delete_buffer_on_destruct(true),
+      buffer(new color_t[other.width * other.height]), width(other.width),
+      height(other.height), pitch(other.width) {
+      overlay_from<other_color_t, overlay>(other, 0, 0, 0, 0, width, height);
+    }
 
     image(image<color_t> &&other)
     : delete_buffer_on_destruct(other.delete_buffer_on_destruct),
@@ -62,7 +75,19 @@ namespace daguerre {
       other.buffer = 0;
     }
 
-    image<color_t> &operator =(const image<color_t> &other) = delete;
+    template <class other_color_t,
+      void overlay(color_t &, const other_color_t &) = default_overlay>
+    image<color_t> &operator =(const image<other_color_t> &other) {
+      if (delete_buffer_on_destruct && buffer)
+        delete[] buffer;
+      delete_buffer_on_destruct = true;
+      width = other.width;
+      height = other.height;
+      pitch = width;
+      buffer = new color_t[width * height];
+      overlay_from<other_color_t, overlay>(other, 0, 0, 0, 0, width, height);
+      return *this;
+    }
 
     image<color_t> &operator =(image<color_t> &&other) {
       if (delete_buffer_on_destruct && buffer)
@@ -84,48 +109,47 @@ namespace daguerre {
       buffer[y * pitch + x] = c;
     }
 
-  };
+    void copy_from(
+      const image<color_t> &other, unsigned to_x, unsigned to_y,
+      unsigned from_x, unsigned from_y, unsigned width, unsigned height) {
 
-  //it is assumed that the regions do not overlap in memory.
+      color_t *to_start = buffer + pitch * to_y + to_x;
-  //copies into [to_x, to_x + width) x [to_y, to_y + height)
+      const color_t *from_start = other.buffer + other.pitch * from_y + from_x;
-  //from [from_x, from_x + width) x [from_y, from_y + height).
-  template <class color_t>
-  void copy_region(
-    image<color_t> &to, unsigned to_x, unsigned to_y,
-    const image<color_t> &from, unsigned from_x, unsigned from_y,
-    unsigned width, unsigned height) {
-
-    color_t *to_start = to.buffer + to.pitch * to_y + to_x;
-    const color_t *from_start = from.buffer + from.pitch * from_y + from_x;
 
       for (unsigned y = 0; y < height; ++y)
         std::memcpy(
-        to_start + to.pitch * y, from_start + from.pitch * y,
+          to_start + pitch * y, from_start + other.pitch * y,
           width * sizeof(color_t));
 
     }
 
-  //it is assumed that the regions do not overlap in memory.
+    template <class other_color_t,
-  //copies into [to_x, to_x + width) x [to_y, to_y + height)
+      void overlay(color_t &, const other_color_t &) = default_overlay>
-  //from [from_x, from_x + width) x [from_y, from_y + height).
+    void overlay_from(
-  template <
+      const image<other_color_t> &other, unsigned to_x, unsigned to_y,
-    class to_color_t, class from_color_t,
+      unsigned from_x, unsigned from_y, unsigned width, unsigned height) {
-    void overlay(to_color_t &dest, const from_color_t &src) = default_overlay>
-  void overlay_region(
-    image<to_color_t> &to, unsigned to_x, unsigned to_y,
-    const image<from_color_t> &from, unsigned from_x, unsigned from_y,
-    unsigned width, unsigned height) {
 
-    to_color_t *to_start = to.buffer + to.pitch * to_y + to_x;
+      color_t *to_start = buffer + pitch * to_y + to_x;
-    const from_color_t *from_start =
+      const other_color_t *from_start =
-      from.buffer + from.pitch * from_y + from_x;
+        other.buffer + other.pitch * from_y + from_x;
 
       for (unsigned y = 0; y < height; ++y)
         for (unsigned x = 0; x < width; ++x)
-        overlay(to_start[to.pitch * y + x], from_start[from.pitch * y + x]);
+          overlay(to_start[pitch * y + x], from_start[other.pitch * y + x]);
 
     }
 
+  };
+
+  template <class color_t>
+  void swap(image<color_t> &a, image<color_t> &b) {
+    std::swap(a.delete_buffer_on_destruct, b.delete_buffer_on_destruct);
+    std::swap(a.buffer, b.buffer);
+    std::swap(a.width, b.width);
+    std::swap(a.height, b.height);
+    std::swap(a.pitch, b.pitch);
+  }
+
   image<hilbert_color> get_hilbert_framebuffer();
 
   bool try_load_ppm(std::FILE *input, image<rgb24> &into);
@@ -159,8 +183,8 @@ namespace daguerre {
         if (ch == 0)
           return;
         if (ch < 128) {
-          overlay_region<target_color_t, color_t, overlay>(
+          target.template overlay_from<color_t, overlay>(
-            target, x, y, glyphs[ch], 0, 0, width, height);
+            glyphs[ch], x, y, 0, 0, width, height);
           x += width;
         }
         ++text;