Added win32 samples (first pass)

renderers/win32_gdi/clay_renderer_gdi.c

@@ -0,0 +1,178 @@
+#include <Windows.h>
+
+
+HDC renderer_hdcMem = {0};
+HBITMAP renderer_hbmMem = {0};
+HANDLE renderer_hOld = {0};
+
+void Clay_Win32_Render(HWND hwnd, Clay_RenderCommandArray renderCommands)
+{
+    bool is_clipping = false;
+    HRGN clipping_region = {0};
+
+    PAINTSTRUCT ps;
+    HDC hdc;
+    RECT rc; // Top left of our window
+
+    GetWindowRect(hwnd, &rc);
+
+    hdc = BeginPaint(hwnd, &ps);
+
+    int win_width = rc.right - rc.left,
+        win_height = rc.bottom - rc.top;
+
+    // Create an off-screen DC for double-buffering
+    renderer_hdcMem = CreateCompatibleDC(hdc);
+    renderer_hbmMem = CreateCompatibleBitmap(hdc, win_width, win_height);
+
+    renderer_hOld = SelectObject(renderer_hdcMem, renderer_hbmMem);
+
+    // draw
+
+    for (int j = 0; j < renderCommands.length; j++)
+    {
+        Clay_RenderCommand *renderCommand = Clay_RenderCommandArray_Get(&renderCommands, j);
+        Clay_BoundingBox boundingBox = renderCommand->boundingBox;
+
+        switch (renderCommand->commandType)
+        {
+        case CLAY_RENDER_COMMAND_TYPE_TEXT:
+        {
+            Clay_Color c = renderCommand->renderData.text.textColor;
+            SetTextColor(renderer_hdcMem, RGB(c.r, c.g, c.b));
+            SetBkMode(renderer_hdcMem, TRANSPARENT);
+
+            RECT r = rc;
+            r.left = boundingBox.x;
+            r.top = boundingBox.y;
+            r.right = boundingBox.x + boundingBox.width + r.right;
+            r.bottom = boundingBox.y + boundingBox.height + r.bottom;
+
+            DrawTextA(renderer_hdcMem, renderCommand->renderData.text.stringContents.chars,
+                      renderCommand->renderData.text.stringContents.length,
+                      &r, DT_TOP | DT_LEFT);
+
+            break;
+        }
+        case CLAY_RENDER_COMMAND_TYPE_RECTANGLE:
+        {
+            Clay_RectangleRenderData rrd = renderCommand->renderData.rectangle;
+            RECT r = rc;
+
+            r.left = boundingBox.x;
+            r.top = boundingBox.y;
+            r.right = boundingBox.x + boundingBox.width;
+            r.bottom = boundingBox.y + boundingBox.height;
+
+            HBRUSH recColor = CreateSolidBrush(RGB(rrd.backgroundColor.r, rrd.backgroundColor.g, rrd.backgroundColor.b));
+
+            if (rrd.cornerRadius.topLeft > 0)
+            {
+                HRGN roundedRectRgn = CreateRoundRectRgn(
+                    r.left, r.top, r.right + 1, r.bottom + 1,
+                    rrd.cornerRadius.topLeft * 2, rrd.cornerRadius.topLeft * 2);
+
+                FillRgn(renderer_hdcMem, roundedRectRgn, recColor);
+                DeleteObject(roundedRectRgn);
+            }
+            else
+            {
+                FillRect(renderer_hdcMem, &r, recColor);
+            }
+
+            DeleteObject(recColor);
+            break;
+        }
+
+        // The renderer should begin clipping all future draw commands, only rendering content that falls within the provided boundingBox.
+        case CLAY_RENDER_COMMAND_TYPE_SCISSOR_START:
+        {
+            is_clipping = true;
+
+            clipping_region = CreateRectRgn(boundingBox.x,
+                                            boundingBox.y,
+                                            boundingBox.x + boundingBox.width,
+                                            boundingBox.y + boundingBox.height);
+
+            SelectClipRgn(renderer_hdcMem, clipping_region);
+            break;
+        }
+
+        // The renderer should finish any previously active clipping, and begin rendering elements in full again.
+        case CLAY_RENDER_COMMAND_TYPE_SCISSOR_END:
+        {
+            SelectClipRgn(renderer_hdcMem, NULL);
+
+            if (clipping_region)
+            {
+                DeleteObject(clipping_region);
+            }
+
+            is_clipping = false;
+            clipping_region = NULL;
+
+            break;
+        }
+
+            // The renderer should draw a colored border inset into the bounding box.
+        case CLAY_RENDER_COMMAND_TYPE_BORDER:
+        {
+           break;
+        }
+
+        default:
+            printf("Unhandled render command %d\r\n", renderCommand->commandType);
+            break;
+        }
+    }
+
+    BitBlt(hdc, 0, 0, win_width, win_height, renderer_hdcMem, 0, 0, SRCCOPY);
+
+    // Free-up the off-screen DC
+    SelectObject(renderer_hdcMem, renderer_hOld);
+    DeleteObject(renderer_hbmMem);
+    DeleteDC(renderer_hdcMem);
+
+    EndPaint(hwnd, &ps);
+}
+
+
+/*
+    Hacks due to the windows api not making sence to use.... may measure too large, but never too small
+*/
+
+#ifndef WIN32_FONT_HEIGHT
+#define WIN32_FONT_HEIGHT (16)
+#endif
+
+#ifndef WIN32_FONT_WIDTH
+#define WIN32_FONT_WIDTH (8)
+#endif
+
+static inline Clay_Dimensions Clay_Win32_MeasureText(Clay_StringSlice text, Clay_TextElementConfig *config, void *userData)
+{
+    Clay_Dimensions textSize = {0};
+
+    float maxTextWidth = 0.0f;
+    float lineTextWidth = 0;
+    float textHeight = WIN32_FONT_HEIGHT;
+
+    for (int i = 0; i < text.length; ++i)
+    {
+        if (text.chars[i] == '\n')
+        {
+            maxTextWidth = fmax(maxTextWidth, lineTextWidth);
+            lineTextWidth = 0;
+            continue;
+        }
+
+        lineTextWidth += WIN32_FONT_WIDTH;
+    }
+
+    maxTextWidth = fmax(maxTextWidth, lineTextWidth);
+
+    textSize.width = maxTextWidth;
+    textSize.height = textHeight;
+
+    return textSize;
+}