feat: add rasterization pipeline

flake.nix

@@ -6,20 +6,24 @@
   outputs = {
     self,
     nixpkgs,
-  } : let system = "x86_64-linux";
+  }: let
+    system = "x86_64-linux";
     pkgs = import nixpkgs {inherit system;};
   in {
     devShells.${system}.default = pkgs.mkShell {
-      nativeBuildInputs = with pkgs;
+      nativeBuildInputs = with pkgs; [
-      [gcc clang -
+        gcc
-          tools lldb
+        clang-tools
+        lldb
 
-              meson ninja pkg -
+        meson
-          config
+        ninja
+        pkg-config
 
         gtk4
 
-                  gdb];
+        gdb
+      ];
 
       shellHook = "";
     };

src/core/primitives.c

@@ -45,3 +45,13 @@ void vektor_polygon_free(VektorPolygon *pg) {
   free(pg->points);
   free(pg);
 }
+
+void vektor_primitivebuffer_add_primitive(VektorPrimitiveBuffer *buffer,
+                                          VektorPrimitive prim) {
+  if (buffer->count >= buffer->capacity) {
+    buffer->capacity = buffer->capacity ? buffer->capacity * 2 : 4;
+    buffer->primitives =
+        realloc(buffer->primitives, sizeof(VektorPrimitive) * buffer->capacity);
+  }
+  buffer->primitives[buffer->count++] = prim;
+}

src/core/primitives.h

@@ -27,7 +27,12 @@ typedef struct {
   double radius;
 } VektorCircle;
 
-typedef enum { LINE, POLYLINE, POLYGON, CIRCLE } VektorPrimitiveKind;
+typedef enum {
+  VEKTOR_LINE,
+  VEKTOR_POLYLINE,
+  VEKTOR_POLYGON,
+  VEKTOR_CIRCLE
+} VektorPrimitiveKind;
 
 typedef struct {
   VektorPrimitiveKind kind;
@@ -47,4 +52,13 @@ VektorPolygon *vektor_polygon_new(void);
 void vektor_polygon_add_point(VektorPolygon *pl, V2 point);
 void vektor_polygon_free(VektorPolygon *pl);
 
+typedef struct {
+  VektorPrimitive *primitives;
+  size_t count;
+  size_t capacity;
+} VektorPrimitiveBuffer;
+
+void vektor_primitivebuffer_add_primitive(VektorPrimitiveBuffer *edges,
+                                          VektorPrimitive edge);
+
 #endif // PRIMITIVES_H_

src/core/raster.c

@@ -1,6 +1,7 @@
 #include "raster.h"
 #include "primitives.h"
 #include "stddef.h"
+#include <stddef.h>
 
 void vektor_edgebuffer_add_edge(EdgeBuffer *buffer, Edge edge) {
   if (buffer->count >= buffer->capacity) {
@@ -10,17 +11,18 @@ void vektor_edgebuffer_add_edge(EdgeBuffer *buffer, Edge edge) {
   buffer->edges[buffer->count++] = edge;
 }
 
-void vektor_edgebuffer_flatten_line(EdgeBuffer *buffer, VektorLine line) {
+void vektor_line_flatten(EdgeBuffer *buffer, VektorLine line) {
   vektor_edgebuffer_add_edge(buffer, (Edge){line.p1, line.p2, 0});
 }
 
-void vektor_edgebuffer_flatten_polyline(EdgeBuffer *buffer, VektorPolyline *line) {
+void vektor_polyline_flatten(EdgeBuffer *buffer, VektorPolyline *line) {
   for (size_t i = 0; i + 1 < line->count; i++) {
-    vektor_edgebuffer_add_edge(buffer, (Edge){line->points[i], line->points[i + 1], 0});
+    vektor_edgebuffer_add_edge(buffer,
+                               (Edge){line->points[i], line->points[i + 1], 0});
   }
 }
 
-void vektor_edgebuffer_flatten_polygon(EdgeBuffer *buffer, VektorPolygon *pg) {
+void vektor_polygon_flatten(EdgeBuffer *buffer, VektorPolygon *pg) {
   size_t n = pg->count;
   if (n < 3)
     return;
@@ -33,25 +35,27 @@ void vektor_edgebuffer_flatten_polygon(EdgeBuffer *buffer, VektorPolygon *pg) {
   }
 }
 
-inline VektorFramebuffer vektor_framebuffer_new(unsigned int W, unsigned int H) {
+inline VektorFramebuffer vektor_framebuffer_new(unsigned int W,
-  VektorFramebuffer fb = {.width = W, .height = H, .pixels = calloc(W * H * 4, 1)};
+                                                unsigned int H) {
+  VektorFramebuffer fb = {
+      .width = W, .height = H, .pixels = calloc(W * H * 4, 1)};
   return fb;
 }
 
-inline void vektor_framebuffer_putpixel(VektorFramebuffer *fb, int x, int y, unsigned char r,
+inline void vektor_framebuffer_putpixel(VektorFramebuffer *fb, int x, int y,
-                      unsigned char g, unsigned char b) {
+                                        VektorColor color) {
   if ((unsigned)x >= fb->width || (unsigned)y >= fb->height)
     return;
 
   int i = (y * fb->width + x) * 4;
-  fb->pixels[i + 0] = r;
+  fb->pixels[i + 0] = color.r;
-  fb->pixels[i + 1] = g;
+  fb->pixels[i + 1] = color.g;
-  fb->pixels[i + 2] = b;
+  fb->pixels[i + 2] = color.b;
-  fb->pixels[i + 3] = 255;
+  fb->pixels[i + 3] = color.a;
 }
 
-void vektor_framebuffer_drawline(VektorFramebuffer *fb, V2 a, V2 b, unsigned char r, unsigned char g,
+void vektor_framebuffer_drawline(VektorFramebuffer *fb, V2 a, V2 b,
-               unsigned char bl) {
+                                 VektorColor color) {
   int x0 = (int)a.x;
   int y0 = (int)a.y;
   int x1 = (int)b.x;
@@ -64,7 +68,7 @@ void vektor_framebuffer_drawline(VektorFramebuffer *fb, V2 a, V2 b, unsigned cha
   int err = dx + dy;
 
   for (;;) {
-    vektor_framebuffer_putpixel(fb, x0, y0, r, g, bl);
+    vektor_framebuffer_putpixel(fb, x0, y0, color);
     if (x0 == x1 && y0 == y1)
       break;
 
@@ -80,15 +84,32 @@ void vektor_framebuffer_drawline(VektorFramebuffer *fb, V2 a, V2 b, unsigned cha
   }
 }
 
-void vektor_framebuffer_drawto(VektorFramebuffer* fb, VektorCanvas* target) {
+void rasterize(VektorFramebuffer *fb, VektorPrimitiveBuffer *prims) {
-  for(int x = 0; x < fb->width; x++) {
+  EdgeBuffer edges = {0};
-    for(int y = 0; y < fb->height; y++) {
+  for (size_t i = 0; i < prims->count; i++) {
+    VektorPrimitive *p = &prims->primitives[i];
 
-      int i = (y * fb->width + x) * 4;
+    switch (p->kind) {
-      target->canvasPixels[i+0] = (guchar)fb->pixels[i+0];
+    case VEKTOR_LINE:
-      target->canvasPixels[i+1] = (guchar)fb->pixels[i+1];
+      vektor_line_flatten(&edges, p->line);
-      target->canvasPixels[i+2] = (guchar)fb->pixels[i+2];
+      break;
-      target->canvasPixels[i+3] = (guchar)fb->pixels[i+3];
+
+    case VEKTOR_POLYLINE:
+      vektor_polyline_flatten(&edges, p->polyline);
+      break;
+
+    case VEKTOR_POLYGON:
+      vektor_polygon_flatten(&edges, p->polygon);
+      break;
+
+    default:
+      // TODO fill in all primitives
+      break;
     }
   }
+
+  for (size_t i = 0; i < edges.count; i++) {
+    vektor_framebuffer_drawline(fb, edges.edges[i].p1, edges.edges[i].p2,
+                                vektor_color_solid(255, 0, 255));
+  }
 }

src/core/raster.h

@@ -2,8 +2,8 @@
 #define RASTER_H_
 
 #include "primitives.h"
-#include "../ui/vektorcanvas.h"
 
+#include "src/util/color.h"
 #include "stddef.h"
 #include "vector.h"
 
@@ -21,9 +21,9 @@ typedef struct {
 
 void vektor_edgebuffer_add_edge(EdgeBuffer *edges, Edge edge);
 
-void vektor_edgebuffer_flatten_line(EdgeBuffer *edges, VektorLine line);
+void vektor_line_flatten(EdgeBuffer *edges, VektorLine line);
-void vektor_edgebuffer_flatten_polyline(EdgeBuffer *edges, VektorPolyline *line);
+void vektor_polyline_flatten(EdgeBuffer *edges, VektorPolyline *line);
-void vektor_edgebuffer_flatten_polygon(EdgeBuffer *buffer, VektorPolygon *line);
+void vektor_polygon_flatten(EdgeBuffer *buffer, VektorPolygon *line);
 
 typedef struct {
   unsigned int width;
@@ -31,14 +31,15 @@ typedef struct {
   unsigned char *pixels; // Flat RGBA8 array
 } VektorFramebuffer;
 
-VektorFramebuffer vektor_framebuffer_new(unsigned int width, unsigned int height);
+VektorFramebuffer vektor_framebuffer_new(unsigned int width,
+                                         unsigned int height);
 
-void vektor_framebuffer_putpixel(VektorFramebuffer *fb, int x, int y, unsigned char r, unsigned char g,
+void vektor_framebuffer_putpixel(VektorFramebuffer *fb, int x, int y,
-               unsigned char b);
+                                 VektorColor color);
 
-void vektor_framebuffer_drawline(VektorFramebuffer *fb, V2 a, V2 b, unsigned char r, unsigned char g,
+void vektor_framebuffer_drawline(VektorFramebuffer *fb, V2 a, V2 b,
-               unsigned char bl);
+                                 VektorColor color);
 
-void vektor_framebuffer_drawto(VektorFramebuffer* fb, VektorCanvas* canvas);
+void rasterize(VektorFramebuffer *fb, VektorPrimitiveBuffer *primitives);
 
 #endif // RASTER_H_

src/main.c

@@ -1,10 +1,12 @@
 #include "gtk/gtk.h"
+#include "src/core/primitives.h"
 #include "stdio.h"
 #include "stdlib.h"
 
 #include "./core/raster.h"
 #include "./ui/uicontroller.h"
 #include "./ui/vektorcanvas.h"
+#include "./util/color.h"
 
 static void on_map(GtkWidget *window, gpointer user_data) {
   vektor_uictrl_map((VektorWidgetState *)user_data);
@@ -22,18 +24,31 @@ void write_ppm(const char *path, const VektorFramebuffer *fb) {
 
 static void activate(GtkApplication *app, gpointer user_data) {
   VektorFramebuffer fb = vektor_framebuffer_new(400, 400);
-  EdgeBuffer edges = {0};
 
-  VektorPolygon pg = *vektor_polygon_new();
+  VektorPolygon triangle = *vektor_polygon_new();
-  vektor_polygon_add_point(&pg, (V2){50, 50});
+  vektor_polygon_add_point(&triangle, (V2){50, 150});
-  vektor_polygon_add_point(&pg, (V2){200, 80});
+  vektor_polygon_add_point(&triangle, (V2){200, 180});
-  vektor_polygon_add_point(&pg, (V2){120, 200});
+  vektor_polygon_add_point(&triangle, (V2){120, 300});
 
-  vektor_edgebuffer_flatten_polygon(&edges, &pg);
+  VektorPolygon star = *vektor_polygon_new();
+  vektor_polygon_add_point(&star, (V2){150, 40});
+  vektor_polygon_add_point(&star, (V2){180, 110});
+  vektor_polygon_add_point(&star, (V2){260, 110});
+  vektor_polygon_add_point(&star, (V2){200, 160});
+  vektor_polygon_add_point(&star, (V2){220, 240});
+  vektor_polygon_add_point(&star, (V2){150, 190});
+  vektor_polygon_add_point(&star, (V2){80, 240});
+  vektor_polygon_add_point(&star, (V2){100, 160});
+  vektor_polygon_add_point(&star, (V2){40, 110});
+  vektor_polygon_add_point(&star, (V2){120, 110});
 
-  for (size_t i = 0; i < edges.count; i++) {
+  VektorPrimitiveBuffer prims = {0};
-    vektor_framebuffer_drawline(&fb, edges.edges[i].p1, edges.edges[i].p2, 0, 0, 0);
+  vektor_primitivebuffer_add_primitive(
-  }
+      &prims, (VektorPrimitive){.kind = VEKTOR_POLYGON, .polygon = &triangle});
+  vektor_primitivebuffer_add_primitive(
+      &prims, (VektorPrimitive){.kind = VEKTOR_POLYGON, .polygon = &star});
+
+  rasterize(&fb, &prims);
 
   VektorWidgetState *widget_state =
       (VektorWidgetState *)malloc(sizeof(VektorWidgetState));
@@ -42,7 +57,7 @@ static void activate(GtkApplication *app, gpointer user_data) {
   VektorCanvas *canvas = (VektorCanvas *)malloc(sizeof(VektorCanvas));
   vektor_canvas_init(widget_state, canvas);
   vektor_canvas_fill(canvas, vektor_color_new(255, 0, 0, 255));
-  vektor_framebuffer_drawto(&fb, canvas);
+  vektor_canvas_drawfrom(&fb, canvas);
   vektor_canvas_update(canvas);
 
   g_signal_connect(widget_state->window, "map", G_CALLBACK(on_map),

src/ui/vektorcanvas.c

@@ -1,5 +1,6 @@
 #include "gtk/gtk.h"
 
+#include "../core/raster.h"
 #include "uicontroller.h"
 #include "vektorcanvas.h"
 
@@ -40,7 +41,7 @@ void vektor_canvas_update(VektorCanvas *canvas) {
                             GDK_PAINTABLE(canvas->canvasTexture));
 }
 
-void vektor_canvas_fill(VektorCanvas *canvas, VektorCanvasColor color) {
+void vektor_canvas_fill(VektorCanvas *canvas, VektorColor color) {
   for (int x = 0; x < VKTR_CANVAS_WIDTH; x++) {
     for (int y = 0; y < VKTR_CANVAS_HEIGHT; y++) {
       int i = (y * VKTR_CANVAS_WIDTH + x) * 4;
@@ -52,7 +53,15 @@ void vektor_canvas_fill(VektorCanvas *canvas, VektorCanvasColor color) {
   }
 }
 
-VektorCanvasColor vektor_color_new(guchar cr, guchar cg, guchar cb, guchar ca) {
+void vektor_canvas_drawfrom(VektorFramebuffer *fb, VektorCanvas *target) {
-  VektorCanvasColor c = {.r = cr, .g = cg, .b = cb, .a = ca};
+  for (int x = 0; x < fb->width; x++) {
-  return c;
+    for (int y = 0; y < fb->height; y++) {
+
+      int i = (y * fb->width + x) * 4;
+      target->canvasPixels[i + 0] = (guchar)fb->pixels[i + 0];
+      target->canvasPixels[i + 1] = (guchar)fb->pixels[i + 1];
+      target->canvasPixels[i + 2] = (guchar)fb->pixels[i + 2];
+      target->canvasPixels[i + 3] = (guchar)fb->pixels[i + 3];
+    }
+  }
 }

src/ui/vektorcanvas.h

@@ -1,6 +1,8 @@
 #ifndef VKTR_CANVAS_H
 #define VKTR_CANVAS_H
 
+#include "../core/raster.h"
+#include "../util/color.h"
 #include "uicontroller.h"
 
 typedef struct VektorCanvas {
@@ -15,17 +17,9 @@ typedef struct VektorCanvas {
   int height;
 } VektorCanvas;
 
-typedef struct VektorCanvasColor {
-  guchar r;
-  guchar g;
-  guchar b;
-  guchar a;
-} VektorCanvasColor;
-
 void vektor_canvas_init(VektorWidgetState *state, VektorCanvas *canvasOut);
 void vektor_canvas_update(VektorCanvas *canvas);
-void vektor_canvas_fill(VektorCanvas *canvas, VektorCanvasColor color);
+void vektor_canvas_fill(VektorCanvas *canvas, VektorColor color);
-
+void vektor_canvas_drawfrom(VektorFramebuffer *fb, VektorCanvas *canvas);
-VektorCanvasColor vektor_color_new(guchar r, guchar g, guchar b, guchar a);
 
 #endif

src/util/color.h

@@ -0,0 +1,23 @@
+#ifndef COLOR_H_
+#define COLOR_H_
+
+typedef struct VektorColor {
+  unsigned char r;
+  unsigned char g;
+  unsigned char b;
+  unsigned char a;
+} VektorColor;
+
+static VektorColor vektor_color_blank = (VektorColor){0, 0, 0, 0};
+
+static inline VektorColor vektor_color_new(unsigned char r, unsigned char g,
+                                           unsigned char b, unsigned char a) {
+  return (VektorColor){r, g, b, a};
+}
+
+static inline VektorColor vektor_color_solid(unsigned char r, unsigned char g,
+                                             unsigned char b) {
+  return (VektorColor){r, g, b, 255};
+}
+
+#endif // COLOR_H_