working for windows

src/MiniFB_internal.c

@@ -4,6 +4,7 @@
 //#define kUseBilinearInterpolation
 
 #if defined(kUseBilinearInterpolation)
+//-------------------------------------
 static uint32_t 
 interpolate(uint32_t *srcImage, uint32_t x, uint32_t y, uint32_t srcOffsetX, uint32_t srcOffsetY, uint32_t srcWidth, uint32_t srcHeight, uint32_t srcPitch) {
     uint32_t incX = x + 1 < srcWidth ? 1 : 0;
@@ -39,6 +40,7 @@ interpolate(uint32_t *srcImage, uint32_t x, uint32_t y, uint32_t srcOffsetX, uin
 #endif
 
 // Only for 32 bits images
+//-------------------------------------
 void 
 stretch_image(uint32_t *srcImage, uint32_t srcX, uint32_t srcY, uint32_t srcWidth, uint32_t srcHeight, uint32_t srcPitch,
               uint32_t *dstImage, uint32_t dstX, uint32_t dstY, uint32_t dstWidth, uint32_t dstHeight, uint32_t dstPitch) {
@@ -75,3 +77,28 @@ stretch_image(uint32_t *srcImage, uint32_t srcX, uint32_t srcY, uint32_t srcWidt
         dstImage += dstPitch;
     }
 }
+
+//-------------------------------------
+void 
+calc_dst_factor(SWindowData *window_data, uint32_t width, uint32_t height) {
+    if (window_data->dst_width == 0) {
+        window_data->dst_width = width;
+    }
+    window_data->factor_x     = (float) window_data->dst_offset_x / (float) width;
+    window_data->factor_width = (float) window_data->dst_width    / (float) width;
+
+    if (window_data->dst_height == 0) {
+        window_data->dst_height = height;
+    }
+    window_data->factor_y      = (float) window_data->dst_offset_y / (float) height;
+    window_data->factor_height = (float) window_data->dst_height   / (float) height;
+}
+
+//-------------------------------------
+void 
+resize_dst(SWindowData *window_data, uint32_t width, uint32_t height) {
+    window_data->dst_offset_x = width  * window_data->factor_x;
+    window_data->dst_offset_y = height * window_data->factor_y;
+    window_data->dst_width    = width  * window_data->factor_width;
+    window_data->dst_height   = height * window_data->factor_height;
+}

src/MiniFB_internal.h

@@ -1,7 +1,7 @@
 #pragma once
 
-#include "MiniFB.h"
+#include <MiniFB.h>
-#include "MiniFB_enums.h"
+#include "WindowData.h"
 
 #define kCall(func, ...)    if(window_data && window_data->func) window_data->func((struct mfb_window *) window_data, __VA_ARGS__);
 #define kUnused(var)        (void) var;
@@ -12,14 +12,15 @@ typedef struct mfb_timer {
     uint64_t    time;
 } mfb_timer;
 
-
 #if defined(__cplusplus)
 extern "C" {
 #endif
-
     extern short int g_keycodes[512];
     void keyboard_default(struct mfb_window *window, mfb_key key, mfb_key_mod mod, bool isPressed);
 
+    void calc_dst_factor(SWindowData *window_data, uint32_t width, uint32_t height);
+    void resize_dst(SWindowData *window_data, uint32_t width, uint32_t height);
+
 #if defined(__cplusplus)
 }
 #endif

src/WindowData.h

@@ -4,6 +4,7 @@
 #include <stdbool.h>
 #include <MiniFB_enums.h>
 
+//-------------------------------------
 typedef struct {
     void                    *specific;
     void                    *user_data;
@@ -23,6 +24,10 @@ typedef struct {
     uint32_t                dst_offset_y;
     uint32_t                dst_width;
     uint32_t                dst_height;
+    float                   factor_x;
+    float                   factor_y;
+    float                   factor_width;
+    float                   factor_height;
 
     void                    *draw_buffer;
     uint32_t                buffer_width;

src/ios/iOSViewDelegate.m

@@ -243,6 +243,7 @@ NSString *g_shader_src = kShader(
     // Respond to drawable size or orientation changes here
     window_data->window_width  = size.width;
     window_data->window_height = size.height;
+    resize_dst(window_data, size.width, size.height);
 
     kCall(resize_func, size.width, size.height);
 }

src/macosx/MacMiniFB.m

@@ -249,14 +249,6 @@ mfb_update_ex(struct mfb_window *window, void *buffer, unsigned width, unsigned
     memcpy(window_data->draw_buffer, buffer, window_data->buffer_stride * window_data->buffer_height);
 #else
     if(window_data->buffer_width != width || window_data->buffer_height != height) {
-        float deltaX = (float) width  / (float) window_data->buffer_width;
-        float deltaY = (float) height / (float) window_data->buffer_height;
-        
-        window_data->dst_offset_x *= deltaX;
-        window_data->dst_offset_y *= deltaY;
-        window_data->dst_width    *= deltaX;
-        window_data->dst_height   *= deltaY;
-
         window_data->buffer_width  = width;
         window_data->buffer_stride = width * 4;
         window_data->buffer_height = height;

src/macosx/OSXWindow.m

@@ -306,6 +306,7 @@
 
         window_data->window_width  = size.width;
         window_data->window_height = size.height;
+        resize_dst(window_data, size.width, size.height);
 
         kCall(resize_func, size.width, size.height);
     }

src/wayland/WaylandMiniFB.c

@@ -739,13 +739,15 @@ mfb_update_ex(struct mfb_window *window, void *buffer, unsigned width, unsigned
         window_data->buffer_height = height;
         window_data->buffer_stride = width * sizeof(uint32_t);
 
-        float deltaX = (float) width  / (float) window_data->buffer_width;
+        // This must be in the resize event but we don't have it for Wayland :(
-        float deltaY = (float) height / (float) window_data->buffer_height;
+        resize_dst(window_data, width, height);
+        // float deltaX = (float) width  / (float) window_data->buffer_width;
+        // float deltaY = (float) height / (float) window_data->buffer_height;
         
-        window_data->dst_offset_x *= deltaX;
+        // window_data->dst_offset_x *= deltaX;
-        window_data->dst_offset_y *= deltaY;
+        // window_data->dst_offset_y *= deltaY;
-        window_data->dst_width    *= deltaX;
+        // window_data->dst_width    *= deltaX;
-        window_data->dst_height   *= deltaY;
+        // window_data->dst_height   *= deltaY;
 
         wl_buffer_destroy(window_data->draw_buffer);
         window_data->draw_buffer = wl_shm_pool_create_buffer(window_data_way->shm_pool, 0, 

src/windows/WinMiniFB.c

@@ -184,12 +184,9 @@ WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) {
 
         case WM_SIZE:
             if (window_data) {
-                window_data->dst_offset_x = 0;
+                window_data->window_width  = LOWORD(lParam);
-                window_data->dst_offset_y = 0;
+                window_data->window_height = HIWORD(lParam);
-                window_data->dst_width = LOWORD(lParam);
+                resize_dst(window_data, LOWORD(lParam), HIWORD(lParam));
-                window_data->dst_height = HIWORD(lParam);
-                window_data->window_width = window_data->dst_width;
-                window_data->window_height = window_data->dst_height;
                 BitBlt(window_data_win->hdc, 0, 0, window_data->window_width, window_data->window_height, 0, 0, 0, BLACKNESS);
                 kCall(resize_func, window_data->dst_width, window_data->dst_height);
             }
@@ -311,11 +308,7 @@ mfb_open_ex(const char *title, unsigned width, unsigned height, unsigned flags)
     window_data_win->wc.lpszClassName = title;
     RegisterClass(&window_data_win->wc);
 
-    if (window_data->dst_width == 0)
+    calc_dst_factor(window_data, width, height);
-        window_data->dst_width = width;
-
-    if (window_data->dst_height == 0)
-        window_data->dst_height = height;
     
     window_data->window_width  = rect.right;
     window_data->window_height = rect.bottom;
@@ -693,6 +686,11 @@ translate_key(unsigned int wParam, unsigned long lParam) {
 bool 
 mfb_set_viewport(struct mfb_window *window, unsigned offset_x, unsigned offset_y, unsigned width, unsigned height) {
     SWindowData     *window_data     = (SWindowData *) window;
+    SWindowData_Win *window_data_win = 0x0;
+
+    if(window_data == 0x0) {
+        return false;
+    }
 
     if (offset_x + width > window_data->window_width) {
         return false;
@@ -707,6 +705,11 @@ mfb_set_viewport(struct mfb_window *window, unsigned offset_x, unsigned offset_y
     window_data->dst_width    = width;
     window_data->dst_height   = height;
 
+    calc_dst_factor(window_data, window_data->window_width, window_data->window_height);
+
+    window_data_win = (SWindowData_Win *) window_data->specific;
+    BitBlt(window_data_win->hdc, 0, 0, window_data->window_width, window_data->window_height, 0, 0, 0, BLACKNESS);
+
     return true;
 }
 

src/x11/X11MiniFB.c

@@ -262,10 +262,7 @@ processEvent(SWindowData *window_data, XEvent *event) {
         {
             window_data->window_width  = event->xconfigure.width;
             window_data->window_height = event->xconfigure.height;
-            window_data->dst_offset_x = 0;
+            resize_dst(window_data, event->xconfigure.width, event->xconfigure.height);
-            window_data->dst_offset_y = 0;
-            window_data->dst_width    = window_data->window_width;
-            window_data->dst_height   = window_data->window_height;
 
             SWindowData_X11 *window_data_x11 = (SWindowData_X11 *) window_data->specific;
             if(window_data_x11->image_scaler != 0x0) {
@@ -336,14 +333,6 @@ mfb_update_ex(struct mfb_window *window, void *buffer, unsigned width, unsigned
     SWindowData_X11 *window_data_x11 = (SWindowData_X11 *) window_data->specific;
 
     if(window_data->buffer_width != width || window_data->buffer_height != height) {
-        float deltaX = (float) width  / (float) window_data->buffer_width;
-        float deltaY = (float) height / (float) window_data->buffer_height;
-        
-        window_data->dst_offset_x *= deltaX;
-        window_data->dst_offset_y *= deltaY;
-        window_data->dst_width    *= deltaX;
-        window_data->dst_height   *= deltaY;
-
         window_data->buffer_width  = width;
         window_data->buffer_stride = width * 4;
         window_data->buffer_height = height;

tests/noise.c

@@ -30,6 +30,9 @@ main()
     g_buffer = (uint32_t *) malloc(g_width * g_height * 4);
     mfb_set_resize_callback(window, resize);
 
+    mfb_set_viewport(window, 50, 50, g_width - 50 - 50, g_height - 50 - 50);
+    resize(window, g_width - 100, g_height - 100);  // to resize buffer
+
     mfb_update_state state;
     do {
         for (i = 0; i < g_width * g_height; ++i) {