cleanup graphics.zig

src/platform/graphics.zig

@@ -660,10 +660,19 @@ pub fn setTexture(id: Texture.Id, opts: SetTextureOptions) void {
         return;
     };
 
-    // TODO: Apply premultiply, will need scratch buffer
+    var scratch = std.heap.ArenaAllocator.init(self.gpa);
-    assert(opts.premultiplied);
 
     var mipchain = opts.mipchain;
+    if (!opts.premultiplied) {
+        var new_mipchain = mipchain.clone(scratch.allocator()) catch |e| {
+            log.warn("Failed to clone mipmap: {}", .{e});
+            return;
+        };
+
+        new_mipchain.premultiplyAlpha();
+
+        mipchain = new_mipchain;
+    }
 
     var image_data: sg.ImageData = .{};
     assert(mipchain.length() <= image_data.mip_levels.len);
@@ -917,12 +926,7 @@ pub fn setSprite(id: Sprite.Id, opts: SetSpriteOptions) void {
             return;
         };
 
-        next_mipchain.copyFromRect(
+        next_mipchain.copyFromRect(opts.mipchain, 0, 0, .initTrunc(rect));
-            opts.mipchain,
-            0, 0,
-            @trunc(rect.pos.x), @trunc(rect.pos.y),
-            @trunc(rect.size.x), @trunc(rect.size.y)
-        );
     } else {
         next_mipchain = opts.mipchain.clone(next_arena.allocator()) catch |e| {
             log.warn("Failed to clone mipchain: {}", .{e});
@@ -931,9 +935,7 @@ pub fn setSprite(id: Sprite.Id, opts: SetSpriteOptions) void {
     }
 
     if (!opts.premultiplied) {
-        for (0..next_mipchain.length()) |index| {
+        next_mipchain.premultiplyAlpha();
-            next_mipchain.getLevel(index).premultiplyAlpha();
-        }
     }
 
     var prev_size: ?Vec2 = null;
@@ -1043,6 +1045,9 @@ fn repackSpritesheetIfNeeded(id: Spritesheet.Id) void {
 // TODO: This function is a bit large, there are some easy things that could be moved to separate function.
 // e.g. extruding padding.
 fn rebuildSpritesheetTextureIfNeeded(id: Spritesheet.Id) void {
+    // TODO: Allow generating mipmaps
+    // https://github.com/floooh/sokol/issues/102#issuecomment-2926566603
+
     const self = &g_state;
     const spritesheet = self.spritesheets.get(id) orelse return;
     if (!spritesheet.needs_texture_rebuild) {
@@ -1095,36 +1100,22 @@ fn rebuildSpritesheetTextureIfNeeded(id: Spritesheet.Id) void {
             );
             level.copyFrom(sprite_level, x, y);
 
+            // TODO: Make `edge_extrusion` amount configurable
+            var edge_extrusion: u32 = 0;
             if (padding > 0) {
-                for (0..sprite_level.width) |ox| {
+                edge_extrusion = 1;
-                    const pixel = level.getPixel(x+ox, y);
-                    for (0..padding) |i| {
-                        @memcpy(level.getPixel(x+ox, y-(i+1)), pixel);
-                    }
             }
 
-                for (0..sprite_level.width) |ox| {
+            if (edge_extrusion > 0) {
-                    const pixel = level.getPixel(x+ox, y+sprite_level.height-1);
+                level.extrudeEdge(
-                    for (0..padding) |i| {
+                    .{
-                        @memcpy(level.getPixel(x+ox, y+sprite_level.height+i), pixel);
+                        .x = x,
-                    }
+                        .y = y,
-                }
+                        .width = sprite_level.width,
-
+                        .height = sprite_level.height,
-                for (0..sprite_level.height) |oy| {
+                    },
-                    const pixel = level.getPixel(x, y+oy);
+                    edge_extrusion
-                    for (0..padding) |i| {
+                );
-                        @memcpy(level.getPixel(x-(i+1), y+oy), pixel);
-                    }
-                }
-
-                for (0..sprite_level.height) |oy| {
-                    const pixel = level.getPixel(x+sprite_level.width-1, y+oy);
-                    for (0..padding) |i| {
-                        @memcpy(level.getPixel(x+sprite_level.width+i, y+oy), pixel);
-                    }
-                }
-
-                // TODO: Add padding to corners.
             }
         }
     }
@@ -1301,6 +1292,22 @@ pub const Image = struct {
         height: u32,
     };
 
+    const Rect = struct {
+        x: u32,
+        y: u32,
+        width: u32,
+        height: u32,
+
+        fn initTrunc(r: Math.Rect) Image.Rect {
+            return .{
+                .x = @trunc(r.pos.x),
+                .y = @trunc(r.pos.y),
+                .width = @trunc(r.size.x),
+                .height = @trunc(r.size.y),
+            };
+        }
+    };
+
     pub fn initAlloc(gpa: Allocator, opts: InitOptions) !Image {
         const pixel_count = opts.width * opts.height;
         const pixel_size = opts.format.pixelSize();
@@ -1385,15 +1392,12 @@ pub const Image = struct {
         source: Image,
         cx: u32,
         cy: u32,
-        source_cx: u32,
+        source_rect: Image.Rect,
-        source_cy: u32,
-        source_width: u32,
-        source_height: u32,
     ) void {
         assert(source.format == self.format);
 
-        for (0..source_height) |oy| {
+        for (0..source_rect.height) |oy| {
-            const source_y = source_cy+oy;
+            const source_y = source_rect.y+oy;
             const dest_y = cy+oy; 
             if (dest_y >= self.height) {
                 continue;
@@ -1402,8 +1406,8 @@ pub const Image = struct {
                 continue;
             }
 
-            for (0..source_width) |ox| {
+            for (0..source_rect.width) |ox| {
-                const source_x = source_cx+ox;
+                const source_x = source_rect.x+ox;
                 const dest_x = cx+ox; 
                 if (dest_x >= self.width) {
                     continue;
@@ -1426,7 +1430,39 @@ pub const Image = struct {
         cx: u32,
         cy: u32,
     ) void {
-        self.copyFromRect(source, cx, cy, 0, 0, source.width, source.height);
+        self.copyFromRect(source, cx, cy, .{ .x = 0, .y = 0, .width = source.width, .height = source.height});
+    }
+
+    pub fn extrudeEdge(self: Image, rect: Image.Rect, size: u32) void {
+        for (0..rect.width) |ox| {
+            const pixel = self.getPixel(rect.x+ox, rect.y);
+            for (0..size) |i| {
+                @memcpy(self.getPixel(rect.x+ox, rect.y-(i+1)), pixel);
+            }
+        }
+
+        for (0..rect.width) |ox| {
+            const pixel = self.getPixel(rect.x+ox, rect.y+rect.height-1);
+            for (0..size) |i| {
+                @memcpy(self.getPixel(rect.x+ox, rect.y+rect.height+i), pixel);
+            }
+        }
+
+        for (0..rect.height) |oy| {
+            const pixel = self.getPixel(rect.x, rect.y+oy);
+            for (0..size) |i| {
+                @memcpy(self.getPixel(rect.x-(i+1), rect.y+oy), pixel);
+            }
+        }
+
+        for (0..rect.height) |oy| {
+            const pixel = self.getPixel(rect.x+rect.width-1, rect.y+oy);
+            for (0..size) |i| {
+                @memcpy(self.getPixel(rect.x+rect.width+i, rect.y+oy), pixel);
+            }
+        }
+
+        // TODO: Add padding to corners.
     }
 };
 
@@ -1562,10 +1598,7 @@ pub const Mipchain = struct {
         source: Mipchain,
         cx: u32,
         cy: u32,
-        source_cx: u32,
+        source_rect: Image.Rect,
-        source_cy: u32,
-        source_width: u32,
-        source_height: u32,
     ) void {
         assert(self.length() == source.length());
 
@@ -1576,13 +1609,21 @@ pub const Mipchain = struct {
                 source_level,
                 cx >> @intCast(index),
                 cy >> @intCast(index),
-                source_cx >> @intCast(index),
+                .{
-                source_cy >> @intCast(index),
+                    .x = source_rect.x >> @intCast(index),
-                source_width >> @intCast(index),
+                    .y = source_rect.y >> @intCast(index),
-                source_height >> @intCast(index),
+                    .width = source_rect.width >> @intCast(index),
+                    .height = source_rect.height >> @intCast(index),
+                }
             );
         }
     }
+
+    pub fn premultiplyAlpha(self: Mipchain) void {
+        for (0..self.length()) |index| {
+            self.getLevel(index).premultiplyAlpha();
+        }
+    }
 };
 
 pub const Texture = struct {