Projection equation and first cube

This commit is contained in:
Abdelrahman Said 2024-06-29 17:11:31 +01:00
parent 6dc609be14
commit f922980232
7 changed files with 107 additions and 19 deletions

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@ -12,6 +12,7 @@ RAYTRACER_SRC="src/window/*.c \
src/scene/*.c \
src/raytracer/*.c \
src/math/*.c \
src/camera/*.c \
"
RASTERISER_SRC="src/window/*.c \
@ -20,6 +21,7 @@ RASTERISER_SRC="src/window/*.c \
src/list/*.c \
src/rasteriser/*.c \
src/math/*.c \
src/camera/*.c \
$WAPP_SRC \
"

15
include/camera/camera.h Normal file
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@ -0,0 +1,15 @@
#ifndef CAMERA_H
#define CAMERA_H
#include "vector/vec.h"
#include "window/window.h"
typedef struct {
vec3f_t position;
vec3f_t rotation;
} camera_t;
vec2i_t project_point(vec3f_t point, const window_t *wnd,
const camera_t *camera, vec3f_t viewport);
#endif // !CAMERA_H

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@ -38,7 +38,8 @@ void clear_window(window_t *wnd, colour_t colour);
void set_pixel(window_t *wnd, i32 x, i32 y, colour_t colour);
void swap_buffers(window_t *wnd);
vec3f_t window_to_viewport(window_t *wnd, i32 x, i32 y, vec3f_t viewport);
vec3f_t window_to_viewport(const window_t *wnd, i32 x, i32 y, vec3f_t viewport);
vec2i_t viewport_to_window(const window_t *wnd, f32 x, f32 y, vec3f_t viewport);
colour_t colour_add_colour(colour_t a, colour_t b);
colour_t colour_mul(colour_t colour, f32 scalar);

15
src/camera/camera.c Normal file
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@ -0,0 +1,15 @@
#include "camera/camera.h"
#include "vector/vec.h"
#include "window/window.h"
vec2i_t project_point(vec3f_t point, const window_t *wnd,
const camera_t *camera, vec3f_t viewport) {
if (point.z == 0.0f) {
return (vec2i_t){.x = 0, .y = 0};
}
f32 x = point.x * viewport.x / point.z;
f32 y = point.y * viewport.y / point.z;
return viewport_to_window(wnd, x, y, viewport);
}

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@ -1,3 +1,4 @@
#include "camera/camera.h"
#include "mem_arena.h"
#include "mem_utils.h"
#include "misc/misc_utils.h"
@ -11,6 +12,12 @@
int main(void) {
colour_t bg =
(colour_t){.rgba.r = 27, .rgba.g = 38, .rgba.b = 79, .rgba.a = 255};
camera_t camera = {
.position = {.x = 0.0f, .y = 0.0f, .z = 0.0f},
.rotation = {.x = 0.0f, .y = 0.0f, .z = 0.0f},
};
vec3f_t viewport = {.x = 1.0f, .y = 1.0f, .z = 1.0f};
window_t window = {0};
if (!init_window(&window, 800, 800, "CG From Scratch Rasteriser")) {
@ -25,14 +32,47 @@ int main(void) {
// i32 h_min = ((i32)window.half_height) * -1;
// i32 h_max = (i32)window.half_height;
triangle_t triangle = {
.p0 = {-200, -250},
.p1 = {200, 50},
.p2 = {20, 250},
.h0 = 0,
.h1 = 0,
.h2 = 1,
};
// The four "front" vertices
vec3f_t vAf = {-2, -0.5, 5};
vec3f_t vBf = {-2, 0.5, 5};
vec3f_t vCf = {-1, 0.5, 5};
vec3f_t vDf = {-1, -0.5, 5};
// The four "back" vertices
vec3f_t vAb = {-2, -0.5, 6};
vec3f_t vBb = {-2, 0.5, 6};
vec3f_t vCb = {-1, 0.5, 6};
vec3f_t vDb = {-1, -0.5, 6};
// The front face
line_t lABf = {project_point(vAf, &window, &camera, viewport),
project_point(vBf, &window, &camera, viewport)};
line_t lBCf = {project_point(vBf, &window, &camera, viewport),
project_point(vCf, &window, &camera, viewport)};
line_t lCDf = {project_point(vCf, &window, &camera, viewport),
project_point(vDf, &window, &camera, viewport)};
line_t lDAf = {project_point(vDf, &window, &camera, viewport),
project_point(vAf, &window, &camera, viewport)};
// The back face
line_t lABb = {project_point(vAb, &window, &camera, viewport),
project_point(vBb, &window, &camera, viewport)};
line_t lBCb = {project_point(vBb, &window, &camera, viewport),
project_point(vCb, &window, &camera, viewport)};
line_t lCDb = {project_point(vCb, &window, &camera, viewport),
project_point(vDb, &window, &camera, viewport)};
line_t lDAb = {project_point(vDb, &window, &camera, viewport),
project_point(vAb, &window, &camera, viewport)};
// The front-to-back edges
line_t lABfb = {project_point(vAf, &window, &camera, viewport),
project_point(vAb, &window, &camera, viewport)};
line_t lBCfb = {project_point(vBf, &window, &camera, viewport),
project_point(vBb, &window, &camera, viewport)};
line_t lCDfb = {project_point(vCf, &window, &camera, viewport),
project_point(vCb, &window, &camera, viewport)};
line_t lDAfb = {project_point(vDf, &window, &camera, viewport),
project_point(vDb, &window, &camera, viewport)};
Arena *arena = NULL;
u64 capacity = 10ull * 1024ull * 1024ull * 1024ull;
@ -51,10 +91,20 @@ int main(void) {
clear_window(&window, bg);
draw_shaded_triangle(&window, arena, triangle,
(colour_t){.colour = 0x00ff00ff});
draw_wireframe_triangle(&window, arena, triangle,
(colour_t){.colour = 0xff008aff});
draw_line(&window, arena, lABf, (colour_t){.colour = 0xffaa00ff});
draw_line(&window, arena, lBCf, (colour_t){.colour = 0xffaa00ff});
draw_line(&window, arena, lCDf, (colour_t){.colour = 0xffaa00ff});
draw_line(&window, arena, lDAf, (colour_t){.colour = 0xffaa00ff});
draw_line(&window, arena, lABb, (colour_t){.colour = 0x00ffaaff});
draw_line(&window, arena, lBCb, (colour_t){.colour = 0x00ffaaff});
draw_line(&window, arena, lCDb, (colour_t){.colour = 0x00ffaaff});
draw_line(&window, arena, lDAb, (colour_t){.colour = 0x00ffaaff});
draw_line(&window, arena, lABfb, (colour_t){.colour = 0xee0099ff});
draw_line(&window, arena, lBCfb, (colour_t){.colour = 0xee0099ff});
draw_line(&window, arena, lCDfb, (colour_t){.colour = 0xee0099ff});
draw_line(&window, arena, lDAfb, (colour_t){.colour = 0xee0099ff});
swap_buffers(&window);

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@ -1,4 +1,5 @@
#include "aliases.h"
#include "camera/camera.h"
#include "raytracer/raytracer.h"
#include "scene/scene.h"
#include "vector/vec.h"
@ -11,11 +12,6 @@
#define RECURSION_DEPTH 3
typedef struct {
vec3f_t position;
vec3f_t rotation;
} camera_t;
i32 main(i32 argc, char *argv[]) {
colour_t bg =
(colour_t){.rgba.r = 27, .rgba.g = 38, .rgba.b = 79, .rgba.a = 255};

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@ -159,7 +159,8 @@ void set_screen_pixel(window_t *wnd, u32 x, u32 y, colour_t colour) {
pixels[index] = colour.colour;
}
vec3f_t window_to_viewport(window_t *wnd, i32 x, i32 y, vec3f_t viewport) {
vec3f_t window_to_viewport(const window_t *wnd, i32 x, i32 y,
vec3f_t viewport) {
return (vec3f_t){
.x = x * viewport.x / wnd->width,
.y = y * viewport.y / wnd->height,
@ -167,6 +168,14 @@ vec3f_t window_to_viewport(window_t *wnd, i32 x, i32 y, vec3f_t viewport) {
};
}
vec2i_t viewport_to_window(const window_t *wnd, f32 x, f32 y,
vec3f_t viewport) {
return (vec2i_t){
.x = x / viewport.x * wnd->width,
.y = y / viewport.y * wnd->height,
};
}
colour_t colour_add_colour(colour_t a, colour_t b) {
f32 alpha = clamp((f32)(a.rgba.a + b.rgba.a), 0.0f, (f32)UINT8_MAX);