diff --git a/main.cpp b/main.cpp index 7cef7fc..3f4d805 100644 --- a/main.cpp +++ b/main.cpp @@ -26,14 +26,6 @@ OK Basic linear transformations - rotation, translation, scaling #include "math.h" #include "stb_image.h" - -// TODO: -// Perspective correct interpolation -// Camera -// Perspective projection -// Texture mapping -// Reading OBJ - struct Face { int p[3]; Vec2 tex[3]; @@ -88,20 +80,22 @@ float EdgeFunction(Vec4 vecp0, Vec4 vecp1, Vec4 p) { FUNCTION void DrawTriangle(Image* dst, Image *src, Vec4 p0, Vec4 p1, Vec4 p2, Vec2 tex0, Vec2 tex1, Vec2 tex2) { - float min_x = (float)(MIN(p0.x, MIN(p1.x, p2.x))); - float min_y = (float)(MIN(p0.y, MIN(p1.y, p2.y))); - float max_x = (float)(MAX(p0.x, MAX(p1.x, p2.x))); - float max_y = (float)(MAX(p0.y, MAX(p1.y, p2.y))); - min_x = MAX(0, min_x) + 0.5f; - min_y = MAX(0, min_y) + 0.5f; - max_x = MIN(dst->x-1, max_x) + 0.5f; - max_y = MIN(dst->y-1, max_y) + 0.5f; + float min_x1 = (float)(MIN(p0.x, MIN(p1.x, p2.x))); + float min_y1 = (float)(MIN(p0.y, MIN(p1.y, p2.y))); + float max_x1 = (float)(MAX(p0.x, MAX(p1.x, p2.x))); + float max_y1 = (float)(MAX(p0.y, MAX(p1.y, p2.y))); + int min_x = (int)MAX(0, floorf(min_x1)); + int min_y = (int)MAX(0, floorf(min_y1)); + int max_x = (int)MIN(dst->x, ceilf(max_x1)); + int max_y = (int)MIN(dst->y, ceilf(max_y1)); //@Todo: Fix the proper rounding //@Todo: Determine whether we need subprecision etc float area = EdgeFunction(p0, p1, p2); for (int y = min_y; y < max_y; y++) { for (int x = min_x; x < max_x; x++) { + int xi = (int)(x + 0.5f); + int yi = (int)(y + 0.5f); float edge1 = EdgeFunction(p0, p1, { (float)x,(float)y }); float edge2 = EdgeFunction(p1, p2, { (float)x,(float)y }); float edge3 = EdgeFunction(p2, p0, { (float)x,(float)y }); @@ -110,6 +104,8 @@ void DrawTriangle(Image* dst, Image *src, Vec4 p0, Vec4 p1, Vec4 p2, float w1 = edge2 / area; float w2 = edge3 / area; float w3 = edge1 / area; + float x_diff = xi - x; + float y_diff = yi - y; #if 1 float u = tex0.x * (w1 / p0.w) + tex1.x * (w2 / p1.w) + tex2.x * (w3 / p2.w); float v = tex0.y * (w1 / p0.w) + tex1.y * (w2 / p1.w) + tex2.y * (w3 / p2.w); @@ -122,10 +118,20 @@ void DrawTriangle(Image* dst, Image *src, Vec4 p0, Vec4 p1, Vec4 p2, float v = tex0.y * w1 + tex1.y * w2 + tex2.y * w3; #endif - int ui = (int)(u * (src->x - 1) + 0.5f); - int vi = (int)(v * (src->y - 1) + 0.5f); - uint32_t pixel = src->pixels[ui + (src->y - 1 - vi) * src->x]; - dst->pixels[x + (dst->y - 1 - y) * dst->x] = pixel; + int ui = (int)(u * (src->x - 2) + 0.5f); + int vi = (int)(v * (src->y - 2) + 0.5f); + uint32_t *pixel = src->pixels + (ui + (src->y - 1 - vi) * src->x); + Vec4 pixelx1y1 = V4ABGR(*pixel); + Vec4 pixelx2y1 = V4ABGR(*(pixel + 1)); + Vec4 pixelx1y2 = V4ABGR(*(pixel - src->x)); + Vec4 pixelx2y2 = V4ABGR(*(pixel + 1 - src->x)); + + Vec4 blendx1 = Lerp(pixelx1y1, pixelx2y1, x_diff); + Vec4 blendx2 = Lerp(pixelx1y2, pixelx2y2, x_diff); + Vec4 result_color = Lerp(blendx1, blendx2, y_diff); + uint32_t color32 = ColorToU32ARGB(pixelx1y1); + + dst->pixels[xi + (dst->y - 1 - yi) * dst->x] = color32; } } } @@ -153,7 +159,7 @@ void DrawLine(Image *dst, float x0, float y0, float x1, float y1) { } int main() { - OS_Init({.window_x=1280, .window_y=720}); + OS_Init({ 1280,720 }); float rotation = 0; Vec3 camera_pos = {0,0,-5}; int x,y,n; diff --git a/math.h b/math.h index 9edd06f..e70f8fb 100644 --- a/math.h +++ b/math.h @@ -195,10 +195,42 @@ Vec3 Cross(Vec3 a, Vec3 b) { FUNCTION uint32_t ColorToU32ARGB(Vec4 a) { - uint8_t r8 = (uint8_t)(a.r * 255.f + 0.5f); - uint8_t g8 = (uint8_t)(a.g * 255.f + 0.5f); - uint8_t b8 = (uint8_t)(a.b * 255.f + 0.5f); - uint8_t a8 = (uint8_t)(a.a * 255.f + 0.5f); + uint8_t r8 = (uint8_t)(a.r * 255.f); + uint8_t g8 = (uint8_t)(a.g * 255.f); + uint8_t b8 = (uint8_t)(a.b * 255.f); + uint8_t a8 = (uint8_t)(a.a * 255.f); uint32_t result = a8 << 24 | r8 << 16 | g8 << 8 | b8; return result; } + +FUNCTION +Vec4 V4ARGB(uint32_t c) { + float a = ((c & 0xff000000) >> 24) / 255.f; + float r = ((c & 0x00ff0000) >> 16) / 255.f; + float g = ((c & 0x0000ff00) >> 8) / 255.f; + float b = ((c & 0x000000ff) >> 0) / 255.f; + Vec4 result = { r,g,b,a }; + return result; +} + +FUNCTION +Vec4 V4ABGR(uint32_t c) { + float a = ((c & 0xff000000) >> 24) / 255.f; + float b = ((c & 0x00ff0000) >> 16) / 255.f; + float g = ((c & 0x0000ff00) >> 8) / 255.f; + float r = ((c & 0x000000ff) >> 0) / 255.f; + Vec4 result = { r,g,b,a }; + return result; +} + +FUNCTION +float Lerp(float a, float b, float t) { + float result = (1.0f - t) * a + t * b; + return result; +} + +FUNCTION +Vec4 Lerp(Vec4 a, Vec4 b, float t) { + Vec4 result = {Lerp(a.x,b.x,t), Lerp(a.y,b.y,t), Lerp(a.z,b.z,t), Lerp(a.w,b.w,t) }; + return result; +} \ No newline at end of file diff --git a/platform.cpp b/platform.cpp index 2e87cb3..621ab61 100644 --- a/platform.cpp +++ b/platform.cpp @@ -60,7 +60,7 @@ void Win32_ScreenInit(int window_x, int window_y) { g_screen_dib = CreateDIBSection(g_window_dc, &bminfo, DIB_RGB_COLORS, (void**)&mem, 0, 0); g_screen_dc = CreateCompatibleDC(g_window_dc); screen.pixels = (uint32_t*)mem; - depth_buffer = (float*)malloc(window_x * window_y * sizeof(float)); + depth_buffer = (float*)malloc((size_t)window_x * (size_t)window_y * sizeof(float)); screen.x = window_x; screen.y = window_y; } @@ -80,7 +80,7 @@ void OS_Init(OSInitArgs i) { wc.lpfnWndProc = WindowProc; wc.hInstance = g_hinstance; wc.lpszClassName = CLASS_NAME; - RegisterClass(&wc); + ASSERT(RegisterClass(&wc)); g_hwnd = CreateWindowEx( 0, // Optional window styles. @@ -95,7 +95,7 @@ void OS_Init(OSInitArgs i) { ); ASSERT(g_hwnd != 0); - ShowWindow(g_hwnd, g_cmdshow); + ShowWindow(g_hwnd, SW_SHOW); RECT rect; GetWindowRect(g_hwnd, &rect); g_window_dc = GetWindowDC(g_hwnd);