SplenkOS/kernel/src/BasicRenderer.cpp

#include "BasicRenderer.h"

BasicRenderer* GlobalRenderer;

BasicRenderer::BasicRenderer(Framebuffer* framebuffer, PSF1_FONT* psf1_Font) {
	targetFramebuffer = framebuffer;
	PSF1_Font = psf1_Font;
	Colour = 0xFFFFFFFF;
	cursorPosition = {0,0};
}

void BasicRenderer::PutChar(char chr, unsigned int xOff, unsigned int yOff) {
	unsigned int* pixPtr = (unsigned int*)targetFramebuffer->BaseAddress;
	char* fontPtr = (char*)PSF1_Font->glyphBuffer + (chr * PSF1_Font->psf1_Header->charsize);
	for (unsigned long y = yOff; y < yOff + 18; y++) {
		for (unsigned long x = xOff; x < xOff+8; x++) {
			
			if ((*fontPtr & (0b10000000 >> (x - xOff))) > 0) {
				*(unsigned int*)(pixPtr + x + (y * targetFramebuffer->PixelsPerScanline)) = Colour;
			}

		}

		fontPtr++;
	}
}

void BasicRenderer::Print(const char* str) {
	unsigned int x = 0;
	char* chr = (char*)str;

	while (*chr != 0) {
		PutChar(*chr, cursorPosition.x, cursorPosition.y);
		cursorPosition.x+=8;

		if (cursorPosition.x + 8 > targetFramebuffer->Width) {
			cursorPosition.x = 0;
			cursorPosition.y += 18;
		}

		chr++;
	}
}

void BasicRenderer::Clear(uint32_t colour) {
	uint64_t fbBase = (uint64_t)targetFramebuffer->BaseAddress;
    uint64_t bytesPerScanline = targetFramebuffer->PixelsPerScanline * 4;
    uint64_t fbHeight = targetFramebuffer->Height;
    uint64_t fbSize = targetFramebuffer->BufferSize;

    for (int verticalScanline = 0; verticalScanline < fbHeight; verticalScanline ++){
        uint64_t pixPtrBase = fbBase + (bytesPerScanline * verticalScanline);
        for (uint32_t* pixPtr = (uint32_t*)pixPtrBase; pixPtr < (uint32_t*)(pixPtrBase + bytesPerScanline); pixPtr ++){
            *pixPtr = colour;
        }
    }
}

void BasicRenderer::Next() {
	cursorPosition.x = 0;
	cursorPosition.y += 16;
}