diff options
| -rw-r--r-- | emcclib.js | 11 |
1 files changed, 6 insertions, 5 deletions
@@ -224,7 +224,7 @@ mergeInto(LibraryManager.library, { * Prepare to do some drawing on the canvas. */ js_canvas_start_draw: function() { - ctx = offscreen_canvas.getContext('2d'); + ctx = offscreen_canvas.getContext('2d', { alpha: false }); update_xmin = update_xmax = update_ymin = update_ymax = undefined; }, @@ -257,7 +257,8 @@ mergeInto(LibraryManager.library, { */ js_canvas_end_draw: function() { if (update_xmin !== undefined) { - var onscreen_ctx = onscreen_canvas.getContext('2d'); + var onscreen_ctx = + onscreen_canvas.getContext('2d', { alpha: false }); onscreen_ctx.drawImage(offscreen_canvas, update_xmin, update_ymin, update_xmax - update_xmin, @@ -403,14 +404,14 @@ mergeInto(LibraryManager.library, { return midpoint_cache[font]; // Find the width of the string - var ctx1 = onscreen_canvas.getContext('2d'); + var ctx1 = onscreen_canvas.getContext('2d', { alpha: false }); ctx1.font = font; var width = (ctx1.measureText(midpoint_test_str).width + 1) | 0; // Construct a test canvas of appropriate size, initialise it to // black, and draw the string on it in white var measure_canvas = document.createElement('canvas'); - var ctx2 = measure_canvas.getContext('2d'); + var ctx2 = measure_canvas.getContext('2d', { alpha: false }); ctx2.canvas.width = width; ctx2.canvas.height = 2*height; ctx2.fillStyle = "#000000"; @@ -493,7 +494,7 @@ mergeInto(LibraryManager.library, { * the screen. */ js_canvas_copy_to_blitter: function(id, x, y, w, h) { - var blitter_ctx = blitters[id].getContext('2d'); + var blitter_ctx = blitters[id].getContext('2d', { alpha: false }); blitter_ctx.drawImage(offscreen_canvas, x, y, w, h, 0, 0, w, h); |