minesweeper: draw colored mine counters

1 files changed, 25 insertions, 22 deletions

diff --git a/src/renderer/RSoftwareBackend.cpp b/src/renderer/RSoftwareBackend.cpp
index 217354b..7bcdd8f 100644
--- a/src/renderer/RSoftwareBackend.cpp
+++ b/src/renderer/RSoftwareBackend.cpp
@@ -75,8 +75,8 @@ RSoftwareBackend::Draw()
             DrawRectangle(entity.rect);
         } break;
 
-        case REntityType_MonoBitmap: {
-            DrawMonoBitmap(entity.bitmap);
+        case REntityType_AlphaBitmap: {
+            DrawAlphaBitmap(entity.bitmap);
         } break;
 
         default:;
@@ -146,7 +146,7 @@ RSoftwareBackend::DrawRectangle(REntity_Rectangle& entity)
 
 
 void
-RSoftwareBackend::DrawMonoBitmap(REntity_MonoBitmap& entity)
+RSoftwareBackend::DrawAlphaBitmap(REntity_AlphaBitmap& entity)
 {
     int32_t x0 = (int32_t)entity.pos.x;
     int32_t y0 = (int32_t)entity.pos.y;
@@ -176,34 +176,37 @@ RSoftwareBackend::DrawMonoBitmap(REntity_MonoBitmap& entity)
     uint32_t gshift = m_canvas.gshift;
     uint32_t bshift = m_canvas.bshift;
 
-    uint8_t* grayscale = (uint8_t*)entity.bitmap.pixels.get() + (-cut_bot * entity.bitmap.w) + (-cut_left);
-    uint32_t* rgba = m_canvas.pixels + y0 * m_canvas.w + x0;
+    uint8_t* alpha_row = (uint8_t*)entity.bitmap.pixels.get() + (-cut_bot * entity.bitmap.w) + (-cut_left);
+    uint32_t* rgba_row = m_canvas.pixels + y0 * m_canvas.w + x0;
     for (int32_t y = y0; y <= y1; y++) {
-        uint8_t *grayscale_pixels = grayscale;
-        uint32_t *rgba_pixels = rgba;
+        uint8_t* alpha = alpha_row;
+        uint32_t* rgba = rgba_row;
         for (int32_t x = x0; x <= x1; x++) {
-            float alpha = *grayscale_pixels / 255.0f;
+            if (*alpha == 0) {
+                alpha++;
+                rgba++;
+                continue;
+            }
 
-            // Todo: we do not want to blend with existing color!
+            float alphaf = *alpha / 255.0f;
 
-            uint32_t rgba_result = *rgba_pixels;
-            float r0 = (rgba_result >> rshift) & 0xff;
-            float g0 = (rgba_result >> gshift) & 0xff;
-            float b0 = (rgba_result >> bshift) & 0xff;
+            float r1 = entity.color.r * alphaf;
+            float g1 = entity.color.g * alphaf;
+            float b1 = entity.color.b * alphaf;
 
-            float r1 = r0 + (entity.color.r - r0)*alpha;
-            float g1 = g0 + (entity.color.g - g0)*alpha;
-            float b1 = b0 + (entity.color.b - b0)*alpha;
+            uint32_t r2 = uint32_t(r1 * 255.0f) << rshift;
+            uint32_t g2 = uint32_t(g1 * 255.0f) << gshift;
+            uint32_t b2 = uint32_t(b1 * 255.0f) << bshift;
 
-            rgba_result = (uint32_t)r1 << rshift | (uint32_t)g1 << gshift | (uint32_t)b1 << bshift;
-            *rgba_pixels = rgba_result;
+            uint32_t rgba_result = r2 | g2 | b2;
+            *rgba = rgba_result;
 
-            grayscale_pixels++;
-            rgba_pixels++;
+            alpha++;
+            rgba++;
         }
 
-        grayscale += entity.bitmap.w;
-        rgba += m_canvas.w;
+        alpha_row += entity.bitmap.w;
+        rgba_row += m_canvas.w;
     }
 }