Add view to basic shader

3 files changed, 20 insertions, 3 deletions

diff --git a/src/matrix.zig b/src/matrix.zig
index 8ce1dfc..49e9b31 100644
--- a/src/matrix.zig
+++ b/src/matrix.zig
@@ -24,6 +24,22 @@ pub fn Matrix(comptime T: type, row_count: usize, col_count: usize) type {
 
         data: [cols]ColT,
 
+        pub fn transform(self: Self, point: ColT) ColT {
+            const other_mat: Matrix(T, 3, 1) = .{ .data = @bitCast(point) };
+            const r = self.multiply(other_mat);
+            return r.col(0);
+        }
+
+        pub fn multScalar(self: Self, val: T) Self {
+            var result = self;
+            for (&result.data) |*c| {
+                for (c) |*r| {
+                    r.* = r.* * val;
+                }
+            }
+            return result;
+        }
+
         pub fn multiply(self: Self, other: anytype) MatMultResult(Self, @TypeOf(other)) {
             const OtherT = @TypeOf(other);
             comptime assert(Self.cols == OtherT.rows);
@@ -112,8 +128,7 @@ pub fn Matrix(comptime T: type, row_count: usize, col_count: usize) type {
         }
 
         pub fn col(self: Self, ci: usize) ColT {
-            const start = ci * rows;
-            return self.data[start .. start + cols];
+            return self.data[ci];
         }
 
         pub fn equals(self: Self, other: Self) bool {
diff --git a/src/shaders/vertex_solid2d.glsl b/src/shaders/vertex_solid2d.glsl
index 874784a..0ff6142 100644
--- a/src/shaders/vertex_solid2d.glsl
+++ b/src/shaders/vertex_solid2d.glsl
@@ -1,6 +1,7 @@
 #version 300 es
 
 uniform mat3 projection;
+uniform mat3 view;
 uniform mat3 model;
 uniform vec3 color;
 
@@ -9,6 +10,6 @@ in vec2 pos;
 out vec4 a_col;
 
 void main() {
-    gl_Position = vec4((projection * model * vec3(pos, 1)).xy, 0, 1);
+    gl_Position = vec4((projection * view * model * vec3(pos, 1)).xy, 0, 1);
     a_col = vec4(color, 1);
 }
diff --git a/src/webgl.zig b/src/webgl.zig
index abd9df4..c4b7af8 100644
--- a/src/webgl.zig
+++ b/src/webgl.zig
@@ -237,6 +237,7 @@ pub const Shaders = struct {
 pub const General2DSolidProgram = Program(
     &.{
         .{ .identifier = "projection", .shader_name = "projection", .kind = .mat3 },
+        .{ .identifier = "view", .shader_name = "view", .kind = .mat3 },
         .{ .identifier = "model", .shader_name = "model", .kind = .mat3 },
         .{ .identifier = "color", .shader_name = "color", .kind = .vec3 },
     },