feat: add box shadows (#16)

1 files changed, 50 insertions, 0 deletions

diff --git a/render/fx_renderer/fx_stencilbuffer.c b/render/fx_renderer/fx_stencilbuffer.c
new file mode 100644
index 0000000..4f57216
--- /dev/null
+++ b/render/fx_renderer/fx_stencilbuffer.c
@@ -0,0 +1,50 @@
+#include <assert.h>
+#include <wlr/render/gles2.h>
+#include <wlr/util/log.h>
+
+#include "include/render/fx_renderer/fx_stencilbuffer.h"
+
+struct fx_stencilbuffer fx_stencilbuffer_create(void) {
+	return (struct fx_stencilbuffer) {
+		.rb = -1,
+		.width = -1,
+		.height = -1,
+	};
+}
+
+void fx_stencilbuffer_init(struct fx_stencilbuffer *stencil_buffer, int width, int height) {
+	bool first_alloc = false;
+
+	if (stencil_buffer->rb == (uint32_t) -1) {
+		glGenRenderbuffers(1, &stencil_buffer->rb);
+		first_alloc = true;
+	}
+
+	if (first_alloc || stencil_buffer->width != width || stencil_buffer->height != height) {
+		glBindRenderbuffer(GL_RENDERBUFFER, stencil_buffer->rb);
+		glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, width, height);
+		stencil_buffer->width = width;
+		stencil_buffer->height = height;
+
+		GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+		if (status != GL_FRAMEBUFFER_COMPLETE) {
+			wlr_log(WLR_ERROR,
+					"Stencil buffer incomplete, couldn't create! (FB status: %i)",
+					status);
+			return;
+		}
+	}
+
+	// Reattach the RenderBuffer to the FrameBuffer
+	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT,
+			GL_RENDERBUFFER, stencil_buffer->rb);
+}
+
+void fx_stencilbuffer_release(struct fx_stencilbuffer *stencil_buffer) {
+	if (stencil_buffer->rb != (uint32_t) -1 && stencil_buffer->rb) {
+		glDeleteRenderbuffers(1, &stencil_buffer->rb);
+	}
+	stencil_buffer->rb = -1;
+	stencil_buffer->width = -1;
+	stencil_buffer->height = -1;
+}