Abdelrahman
50b8c6dd0a
Reviewed-on: #1 * Start implementing shaders and move vector code to dedicated files * Extract shader into its own header * Ensure pixel coordinates are within bounds * Refactor shader code and implement fragment shaders * Create shaders * Reorganise code Co-authored-by: Abdelrahman <said.abdelrahman89@gmail.com> Co-committed-by: Abdelrahman <said.abdelrahman89@gmail.com>
94 lines
2.3 KiB
C
94 lines
2.3 KiB
C
#include "img.h"
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#include "aliases.h"
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#include "mem_arena.h"
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#include "pam.h"
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#include "utils.h"
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#include <stdbool.h>
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#include <stddef.h>
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#include <string.h>
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internal i64 calculate_pixel_index(Buffer *buffer, u64 x, u64 y, u64 base_size);
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bool _init_buffer(Arena *arena, Buffer *buffer, u64 base_size) {
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if (!arena || !buffer || buffer->width == 0 || buffer->height == 0) {
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return false;
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}
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u64 size = buffer->width * buffer->height * base_size;
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buffer->buf = wapp_mem_arena_alloc(arena, size);
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return buffer->buf != NULL;
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}
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u8 *_get_pixel(Buffer *buffer, u64 x, u64 y, u64 base_size) {
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i64 idx = calculate_pixel_index(buffer, x, y, base_size);
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if (idx == -1) {
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idx = 0;
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}
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return ((u8 *)(buffer->buf)) + idx;
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}
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void _set_pixel(Buffer *buffer, u64 x, u64 y, void *value, u64 base_size) {
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i64 idx = calculate_pixel_index(buffer, x, y, base_size);
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if (idx == -1) {
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return;
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}
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memcpy(((u8 *)(buffer->buf)) + idx, value, base_size);
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return;
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}
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void _clear_buffer(Buffer *buffer, void *value, u64 base_size) {
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for (u64 y = 0; y < buffer->height; ++y) {
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for (u64 x = 0; x < buffer->width; ++x) {
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_set_pixel(buffer, x, y, value, base_size);
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}
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}
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}
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void draw_line(Image *img, u64 x0, u64 y0, u64 x1, u64 y1, Colour colour) {
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u64 dx = absolute((i64)x1 - (i64)x0);
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u64 dy = absolute((i64)y1 - (i64)y0);
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f32 t = 0.0f;
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i64 x = 0;
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i64 y = 0;
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if (dx > dy) {
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if (x0 > x1) {
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swap(u64, x0, x1);
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swap(u64, y0, y1);
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}
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for (u64 x = x0; x < x1; ++x) {
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t = (f32)(x - x0) / (f32)(x1 - x0);
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y = (i64)y0 + ((i64)y1 - (i64)y0) * t;
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set_pixel(img, x, y, &colour);
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}
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} else {
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if (y0 > y1) {
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swap(u64, x0, x1);
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swap(u64, y0, y1);
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}
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for (u64 y = y0; y < y1; ++y) {
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t = (f32)(y - y0) / (f32)(y1 - y0);
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x = (i64)x0 + ((i64)x1 - (i64)x0) * t;
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set_pixel(img, x, y, &colour);
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}
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}
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}
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void save_image(const Image *img, const char *filename) {
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write_p7_image(img->width, img->height, (u8 *)(img->buf), filename);
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}
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internal i64 calculate_pixel_index(Buffer *buffer, u64 x, u64 y,
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u64 base_size) {
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if (x < 0 || y < 0 || x >= buffer->width || y >= buffer->height) {
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return -1;
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}
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return (y * buffer->width + x) * base_size;
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}
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