Restore support for the Nokia N-Gage (#12148)

src/render/ngage/SDL_render_ops.cpp

@@ -0,0 +1,152 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "SDL_internal.h"
+
+#include <3dtypes.h>
+#include "SDL_render_ops.hpp"
+
+void ApplyColorMod(void *dest, void *source, int pitch, int width, int height, SDL_FColor color)
+{
+    TUint16 *src_pixels = static_cast<TUint16 *>(source);
+    TUint16 *dst_pixels = static_cast<TUint16 *>(dest);
+
+    TFixed rf = Real2Fix(color.r);
+    TFixed gf = Real2Fix(color.g);
+    TFixed bf = Real2Fix(color.b);
+
+    for (int y = 0; y < height; ++y)
+    {
+        for (int x = 0; x < width; ++x)
+        {
+            TUint16 pixel = src_pixels[y * pitch / 2 + x];
+            TUint8 r = (pixel & 0xF800) >> 8;
+            TUint8 g = (pixel & 0x07E0) >> 3;
+            TUint8 b = (pixel & 0x001F) << 3;
+            r = FixMul(r, rf);
+            g = FixMul(g, gf);
+            b = FixMul(b, bf);
+            dst_pixels[y * pitch / 2 + x] = (r << 8) | (g << 3) | (b >> 3);
+        }
+    }
+}
+
+void ApplyFlip(void* dest, void* source, int pitch, int width, int height, SDL_FlipMode flip)
+{
+    TUint16* src_pixels = static_cast<TUint16*>(source);
+    TUint16* dst_pixels = static_cast<TUint16*>(dest);
+
+    for (int y = 0; y < height; ++y)
+    {
+        for (int x = 0; x < width; ++x)
+        {
+            int src_x = x;
+            int src_y = y;
+
+            if (flip & SDL_FLIP_HORIZONTAL)
+            {
+                src_x = width - 1 - x;
+            }
+
+            if (flip & SDL_FLIP_VERTICAL)
+            {
+                src_y = height - 1 - y;
+            }
+
+            dst_pixels[y * pitch / 2 + x] = src_pixels[src_y * pitch / 2 + src_x];
+        }
+    }
+}
+
+void ApplyRotation(void* dest, void* source, int pitch, int width, int height, TFixed center_x, TFixed center_y, TFixed angle)
+{
+    TUint16* src_pixels = static_cast<TUint16*>(source);
+    TUint16* dst_pixels = static_cast<TUint16*>(dest);
+
+    TFixed cos_angle = 0;
+    TFixed sin_angle = 0;
+
+    if (angle != 0)
+    {
+        FixSinCos(angle, sin_angle, cos_angle);
+    }
+
+    for (int y = 0; y < height; ++y)
+    {
+        for (int x = 0; x < width; ++x)
+        {
+            // Translate point to origin.
+            TFixed translated_x = Int2Fix(x) - center_x;
+            TFixed translated_y = Int2Fix(y) - center_y;
+
+            // Rotate point (clockwise).
+            TFixed rotated_x = FixMul(translated_x, cos_angle) + FixMul(translated_y, sin_angle);
+            TFixed rotated_y = FixMul(translated_y, cos_angle) - FixMul(translated_x, sin_angle);
+
+            // Translate point back.
+            int final_x = Fix2Int(rotated_x + center_x);
+            int final_y = Fix2Int(rotated_y + center_y);
+
+            // Check bounds.
+            if (final_x >= 0 && final_x < width && final_y >= 0 && final_y < height)
+            {
+                dst_pixels[y * pitch / 2 + x] = src_pixels[final_y * pitch / 2 + final_x];
+            }
+            else
+            {
+                dst_pixels[y * pitch / 2 + x] = 0;
+            }
+        }
+    }
+}
+
+void ApplyScale(void* dest, void* source, int pitch, int width, int height, TFixed center_x, TFixed center_y, TFixed scale_x, TFixed scale_y)
+{
+    TUint16* src_pixels = static_cast<TUint16*>(source);
+    TUint16* dst_pixels = static_cast<TUint16*>(dest);
+
+    for (int y = 0; y < height; ++y)
+    {
+        for (int x = 0; x < width; ++x)
+        {
+            // Translate point to origin.
+            TFixed translated_x = Int2Fix(x) - center_x;
+            TFixed translated_y = Int2Fix(y) - center_y;
+
+            // Scale point.
+            TFixed scaled_x = FixDiv(translated_x, scale_x);
+            TFixed scaled_y = FixDiv(translated_y, scale_y);
+
+            // Translate point back.
+            int final_x = Fix2Int(scaled_x + center_x);
+            int final_y = Fix2Int(scaled_y + center_y);
+
+            // Check bounds.
+            if (final_x >= 0 && final_x < width && final_y >= 0 && final_y < height)
+            {
+                dst_pixels[y * pitch / 2 + x] = src_pixels[final_y * pitch / 2 + final_x];
+            }
+            else
+            {
+                dst_pixels[y * pitch / 2 + x] = 0;
+            }
+        }
+    }
+}